Sunday 29 January 2017

Triumph Trident


The Trident actually beat the Honda CB750 to the marketplace back in 1968. This was a time when Triumph were famous for building light, fast, vibratory and weird handling big twins. The Trident was in a similar vein except that it was then a heavy, fast, vibratory and weird handling triple.

Using many engine components that stretched all the way back to the original vertical twin design of 1937, that the Trident engine actually made it from the drawing board to the production line was, in itself, a great shock and surprise to anyone who knows anything about engineering design.

Thus, the most surprising thing about the Trident is that it can be such good fun out on the road. The result one guesses of the engineering input of some of the long suffering engineers who had to work miracles with limited funds and out of date machinery. This is, of course, no excuse for the poor characteristics that the Trident shows in the harsh light of ownership.

The OHV engine has marginally long stroke dimensions of 67 x 70mm, develops 58hp and ls basically a Triumph twin with an extra piston and cylinder thrown on. Although many engine components are similar to the twin most of them are not interchangeable, which in the end rather made the whole scam a bit pointless. Much better to have started with a clean sheet of paper.

The first model had drum brakes similar in design to the twins, these were changed for conical hubs in '71, but it wasn't until '73 that a single disc was able to cope with the 470lb of steel and alloy. The '71 bike tested was fitted with the later disc and earlier weird if unique silencers.

It was not until 1975 and the introduction of the better T160 that the Trident gained the luxury of an electric starter. This particular example delighted in refusing to start on occasions. Even threatening the thing with a large hammer had no effect.

Whether this was a result of wiring defects or the poor quality of the contact breaker assembly I could not say. But poor starting is a well known problem among Trident owners. When the bike was in a good mood, it would explode into a meaty growl after three of four fairly desperate kicks.

Two problems immediately arise in trying to engage first gear. The clutch lever requires the use of molegrips to actually get the lever back to the handlebars and the clutch plates suffer from drag when the oil is cold. Like a 1910 Triumph twin, the Trident has to be kicked over with ignition switched off and clutch pulled in, to free the plates. The degree of drag is much greater than on, say, old Honda twins when first can be engaged, with the front brake on to stop the bike leaping forward. Try that on the Trident and the engine stalls with a deal of nasty noises.

The three Amal carbs need very regular balancing (100 to 500 miles) to achieve a regular tick-over. The low level of power development really doesn't justify the presence of so many carbs.

Blipping the throttle doesn't send the rev counter needle immediately flicking into the red, but the noise from the exhaust is quite exciting; triples and big vee twins have always made the most interesting sounds. First gear engages with an almost BMW type clunk, even with the clutch plates freed.

The bike won't take off with less than two and a half grand on the clock. The triplex primary chain and tortuous path through the gearbox means there's quite a lot of slop in the transmission. Whack open the throttle in first and the bars go a little light, the back end squats down and the vibration through the bars, footrests and petrol tank is more than a little noticeable. Not as bad as a Triumph twin but more intrusive than one of the old Honda fours.

The gearchange action isn't light but it is positive. Wear in the box makes the second to third change difficult and finding neutral at a standstill almost impossible. The primary chain would be in trouble trying to transmit half the Trident's power - it is noisy, absorbs huge amounts of power and wrecks both its tensioner and itself. Careful maintenance and regular oil changes give it a life of around ten thousand miles.

The Trident feels top heavy in town, the petrol tank is too wide, the seat height too high and the throttle and clutch too heavy. The steering geometry is set up to suit high speed handling in a similar manner to the twin, but the triple has too much weight to get away with this and retain the low speed agility that the twin was justly famous for.

The Trident needs brute force to drag it through traffic at a decent pace, but it is helped by some feedback from the road and a sensitive disc brake. Kids on even restricted 125s can make the triple look silly in built up areas.

The Trident only begins to make sense on fast A roads. Those relatively wide, sweeping bends let the bike's heritage shine through. In these conditions it can show a clean pair of exhausts pipes to Honda's CB750, although to be fair to the Japs, most of the modern 550s will make the Trident look very silly.

There's a nice surge of power around five grand, the bike will accelerate up to the ton in top gear with relative ease, higher speeds are a product of excessive vibes, an uncomfortable riding stance and handling that can do some very nasty things if the power is suddenly backed off.

The single downtube frame was a sort of scaled up sixties Bonnie frame, that shared with it poor support for the swinging arm. In the early twin, this used to verge on the suicidal but was improved by adding plates between engine and frame that held the outer ends of the swinging arm spindle. A similar set up is used on the Trident, but the frame still relies on a basically weak central saddle tube for some of its rigidity, with the result that the swinging arm can thrash about at high speeds.

For a lot of the time the Trident feels commendably secure, much better than the Honda four, but combine a bumpy curve with the sudden need to change direction and the reality of the Trident's design - too much weight carried too high - suddenly makes themselves felt. The back end wriggles and sometimes the front forks join in, the handlebars flip back and forth. Nothing as bad as a Kawasaki triple, but there is a lot of mass involved here and it does need plenty of muscle to keep it under control.

Motorway cruising was no problem. Up to 85mph vibes were acceptable, between 85 and 105mph the vibration became much worst and, at times, felt as if the whole plot was going to fall apart. Riding at this kind of speed for any length of time made the engine overheat, the valve gear make enough clatter to silence the exhausts and blew every bulb on the bike. From 105 to 120mph things smoothed out again, but the bike couldn't hold this speed against headwinds or hills.

Wringing the last few mph out of the bike brought back the vibration in its most intrusive form, it felt as if every moving part in the engine was about to self destruct, the mirrors were a useless blur, the instruments were gyrating wildly and the engine sounded as if all the ball bearings had shaken loose.

Top speed varies from model to model and ranges from 120 to 130mph, this particular bike with forty grand and two rebuilds, was unhappy going past a true 120mph. Above 100mph the bike goes into a gentle weave even on flat, smooth roads. This weave gets worst as speed increases but it never switches into a speed wobble even on bald tyres. Although riding on bald tyres in the wet is not a good idea as the weight of the bike doesn't make it easy to pull the Trident out of a slide.

Riding in the wet would have been quite pleasant as the bike has a secure feel and a reasonable disc, but the engine likes to try to run on two or even one cylinder. If the engine cuts out in a corner in the wet the sudden loss of power can have the back wheel swinging off line. Some Trident owners are of the opinion that this is just good clean fun...

The disc brake was in trouble knocking off speed from 100mph plus speeds, but was otherwise as good as any Jap disc of the period and much safer than earlier drums fitted to the Trident. Disc pads last for about 7500 miles and are quite easy to replace.

Fuel economy is not good. Even the most moderate use does no better than 50mpg. At 80mph it averages 42mpg, at 100mph it's down to 35mpg and really flat out a frightening 28mpg. Fuel averages out between 38 and 45mpg. The four gallon tank gives a range of about 150 miles before reserve. Chain wear isn't too good, either. Between five and eight grand depending on use and maintenance.

The engine has a number of problems arising from the basic design and others from a lack of regular maintenance. The exhaust valves like to burn out due to overheating, especially those of the centre cylinder.

Maintenance every 500 miles helps but the only real solution is to ride slowly. The primary chain has already been mentioned. The clutch likes to burn out, but it's quite cheap to repair. Some engines seize up without warning, oil changes every two grand help together with regular filter changes. The contact breakers fall apart and the advance/retard unit sticks, making starting impossible.

There are other minor problems with pushrods, tappets, camshafts and  gearboxes. The Trident needs lots of attention to stop it giving trouble, but spares are plentiful and cheap when compared with Jap stuff.

The BSA version, the Rocket 3, had a similar engine with the cylinders canted forward and its own stronger frame that wasn't so keen on shaking its back end. The Rocket 3 was finished off in '72 and its relative rarity has gained it cult status and higher prices.

The BSA engine reappeared in the T160 with an electric start thrown on for good measure. The new Trident had an engine with some of the problems sorted out (going as far as was possible without redesigning the engine) and an uprated chassis. Although the new bike weighed even more than the T150 (510lbs) it handled better and really was the bike Triumph should have introduced in '68. In the mid-seventies the demise of the UK industry had gone so far there was little hope for the bike. The T160 is even more expensive than the old bike but a much more usable machine.

Engine life of the T150 varies enormously, depending on maintenance and riding technique. Really thrashed and neglected engines will need a major rebuild by ten grand, at the very least including a complete top end overhaul, a rebore & primary chain. The highest mileage that I could find in which the motor has not been taken apart was 35000 miles. There are a few bikes that have done over a hundred grand, but these have had most of the internals replaced since leaving the factory, at least once if not two or three times.

The Trident engine is not easy to work on, and requires a great deal of attention to detail in reassembly to avoid another early rebuild. Norman Hyde is the leading supplier of spare parts, tuning goodies and big bore kits. This stuff has a pretty good reputation and filling up the engine with all the appropriate bits and pieces makes it much stronger and longer lived.

Prices vary between £750 and £1500, although some people try to demand as much as three grand for so called immaculate examples. Finding a bike for £750 will be hard going but not impossible.

Noisy top-ends and primary chains are the most obvious symptoms of an ill engine. An engine on the way out will also make lots of vibes at all revs and have smoke coming out of the silencers. It's quite hard to disguise the effects of abuse, unlike the twin which will just keep going to the last, expensive moment. It should be possible to buy, something that's running well for around a grand, although it'll probably have a few non-standard parts fitted.

Having ridden this Trident and a few other examples, I can appreciate why some people like them so much - on the right roads the bike really shifts for a heavyweight multi. The fact that the Japs have redefined the multi market with lighter an more powerful bikes rather leaves the Trident gasping for beath.

The bike never had much to offer the economy-minded rider and now doesn't have the performance to cut it amongst the new breed  of 550s (or even 400s). It doesn't offer much more performance than the twins, and isn't that cheap to run.

Johnny Malone

Sunday 22 January 2017

Loose Lines [Issue 4]

In between repairing the roof, consuming large quantities of orange tablets (Vitamin C) and thinking strange thoughts about astoundingly beautiful Thai girls, I spend the odd second or two considering the sad state of the motorcycle industry. These thoughts are usually warped by the knowledge that the first company to actually use the modern design and manufacturing techniques that are available to the actual benefit of the rider will reap rich rewards as they clean up the market. That the Japs have so far failed to make the right machines will come as no surprise to anyone who has had the misfortune to work for a large multinational company.

In my more hallucinatory moments I even labour under the grave misapprehension that I could either sell such an obvious design to the Japs or use it in a solo effort to revive the British motorcycle industry. Such thoughts are soon shattered by even the shortest exposure to the reality of UK industry, where its managers appear trained to find a 101 reasons why they shouldn't do something, rather than thinking in a vaguely positive manner.

The problem with new motorcycles is that they offer few advantages and many inferiorities to the secondhand stuff. Despite the advertising blurb, the factories really need to go back to the drawing board and redefine the middleweight motorcycle. How does 120mph, 80mpg, 350lbs and tyres, brake pads and chains that all last at least 20000 miles sound? And an engine with 5000 mile service intervals that lasts for 100000 miles. Good enough to make you think about deserting the secondhand camp and start pestering your bank manager?

To achieve such a design would be neither cheap nor easy. Certainly, I wouldn't claim to be able to produce such a machine out of my garden shed, but if I had the largest concentration of engineering talent and computer power in the world, then I'd have a jolly good try. If I were in charge of Yamaha, for instance, I'd be half way there already. Their late sixties XS650 twin could manage 110mph and 60mpg. The engine is famous for being tough and long lasting.

What it desperately needed, and never got over its twenty years of life, was a new cylinder head. Although the engine really needs a much shorter stroke to make maximum use of the cylinder head shape (the larger bore giving more room for larger valves), it'll probably be possible to get away with the stock dimensions. Valve timing would be radically altered in the search for greater efficiency. Valve clearance would be set U placing the rockers on eccentric shafts, increasing accuracy and lowering valvegear mass. Such a system would need minimal attention an would be simple to adjust. The twin carbs would be replaced by a single CV unit, making the engine smoother, more efficient and removing the tedious business of balancing carbs. The actual optimisation of all the various factors that control the efficiency of cylinder head design would soon be sorted by a pack of Jap designers using the latest in engine diagnostic equipment.

The XS engine has pistons that move in unison and produces some vibration, but the build quality of the engine means that this vibration is partially absorbed and doesn't cause bits and pieces to fall off the engine. Changing to a 180° crankshaft would decrease vibes but because of the uneven firing pulses a single carb wouldn't work properly. The rest of the engine is pretty tough, but the relative simplicity of its design would make it easy to absorb the cost of tightening up on all the machining tolerances in the engine, to increase efficiency. with its low mass and redesigned combustion chamber, it will be able to get away with using a mere four gears. The final drive chain would be replaced With a rubber belt, which, these days, have progressed to the stage where they can last for 25000 miles and need minimal attention.

These relatively minor changes to the engine and transmission will have left us with a bike capable of around 110mph and 70mpg. The rest of the performance and economy will come from careful design of the aerodynamics and drastic pruning of the mass. With a vertical twin engine it's relatively easy to design a chassis that has both a low centre of gravity and a low mass. A steel frame is preferable to alloy for a road bike as it is more resistant to the occasional off road excursion and can be bent back into shape after an accident.

Because of the low mass and low centre of gravity, frame geometry can be chosen to suit high speed riding without worrying over low speed manoeuvrability. The suspension will be conventional twin rear shocks and non-adjustable front forks. The important difference to the usual fare would be quality of construction and the high damping.

Alloy drum brakes replace discs, using the latest pad materials for improved efficiency and longer life (at least twenty grand). Alloy rims and stainless steel spokes replace cast wheels for ease of crash repair. The combination of drum and spoked wheels should weigh in rather less than cast wheels with discs saving on unsprung mass.

One of those neat alloy swinging arms with eccentric chain adjusters replaces the usual steel item, not least because an out of line wheel will quickly ruin the rubber belt final drive. To save weight and improve efficiency the exhuast will be two into one made out of stainless steel, while the silencer will be alloy.

The whole of the design can then be pulled together by an efficient half fairing moulded into the five gallon alloy petrol tank. Something on the lines of the top half of an RS BMW fairing would do just fine. The fairing will give total hand and upper body protection, while the tank will be sculptured to take the rider‘s knees out of the air stream and protect the leg in the event of the bike falling over.

The narrowness of the engine and efficiency of the shape of the fairing should allow the bike to make it all the way up to 120mph while improving the fuel efficiency to let the bike average 80mpg. Doubtless, readers would add bits and pieces to accommodate their own needs and personal perversions, but the basic machine would have so many fundamental points in its favour that it could take it all in its stride.

Even the perennial problem of tyre wear would be partially solved. The belt drive would help deliver the power smoothly, the aerodynamic fairing would reduce the actual power needed and the low mass would minimise the stresses on the tyres. The rigid frame and top quality suspension would mean that the tyre would only have to worry over adhesion and not have to be designed to stop the bike going into speed wobbles.

Electronic ignition, single carb, automatic chain tensioner and high tech valve gear would reduce regular maintenance to an oil and filter change every few thousand miles. Because it's only a twin, all the engine components can be made of higher grade alloy to increase the life of the engine from 75 to 100000 miles.

An impossible dream? I simply refuse to accept that if British Leyland can update what was basically the Morris Minor engine into the 90mph/50mpg Metro, then the might of the Jap factories can't produce a similar improvement in bike design.

Bill Fowler

Saturday 21 January 2017

Suzuki GT750


Like many other GT750 owners, I was a little shocked and upset by the harsh comments of the editor on this fine machine. My only consolation was that I hadn't paid a silly price for mine.

I was fortunate in paying only £100 for the bike. True, it didn't actually run, but the previous owner had assured me that it was working OK when he'd become fed up with bikes and stuck the Suzi at the back of his garage. As the owner had agreed to deliver the bike to my doorstep I couldn't really complain over the price.

I took out the three plugs, looking down the holes and spinning the back wheel with the bike in gear, showed that the pistons hadn't seized up and it made some promising noises. I changed the engine and gearbox oil, fitted some new plugs and a new battery.

There were no lights, horn or sparks. I traced this fault to a corroded earth strap. Much to my excitement, the lights and horn worked, but still no sparks. I traced the ignition wires from the manual, tried all the spade connectors until I achieved a nice fat blue spark.

As with most two strokes the compression is low, so it's easy to leap up and down on the kickstart. The watercooled two stroke triple doesn't have much compression, so it's not too difficult. The engine made some inspiring noises but after twenty kicks it still hadn't come alive. Then I noticed that two of the spark plug leads looked like they were on the wrong way around.

I swapped them over, and it sounded like it was starting to fire on one cylinder. Out with the plugs, wire brush them clean and heat them over the gas stove. Back in the engine before they get cold, and the thing started second kick.

Blipping the throttle to keep the engine from cutting out, resulted in clouds of blue smoke. This cleared after a minute or two and the engine settled down to a regular tick over at about twelve hundred. It was on with the gloves and the helmet for a quick thrash around the block. The tyres had gone hard and slipped if I leaned over and the disc brakes didn't work.

By the time I'd purchased two new tyres, a chain and two sets of disc pads, I'd almost spent another hundred quid. These didn't exactly transform the bike, but they made it relatively safe to venture out into the Kent back lanes. The pattern pads took half an hour to work in the wet (so did the stock ones... Ed) and the rear shocks and swinging arm were worn out. Over bumpy roads this wasn't too much fun and when I got the bike up to an indicated 110mph it disgraced Itself by going into a tank slapper.

Unlike the editor and various friends, my response was blind panic and shoving on the brakes. The effect is hard to describe, the bike seemed to buckle and squirm underneath me, before I knew it I was on the other side of the road heading straight towards the oncoming traffic. Luckily (?), it continued leftwards, hitting a patch of gravel on the side of the road. By this time, speed was down to about sixty; by the time I actually fell off it was down to thirty.

The bike went back across the road while I rolled along some convenient grass. Much to my surprise the Suzi missed the cars and landed with only a few dents. I escaped with a bruised thigh and ego. Careful examination of the swinging arm revealed a huge amount of free play. The plastic bushes were actually cracked and the spindle scored. I found a spindle in the breakers and spent an afternoon fitting new shims and bushes. I also fitted a secondhand set of Koni shocks. I can take a hint...

With the rear end sorted, I next had to start worrying over the front forks which would dive, buckle and twist whenever I braked really hard. I tried some heavier oil and this helped a little. I didn't want the hassle of stripping the forks to fit heavier springs, so I settled for a fork brace. This took another afternoon to fit because it tended to jam the forks, but I eventually made it work OK.

These modifications still didn't make the Suzi perfect, but it was now quite predictable. My next stage was to try to reduce the mass by replacing as much metal as possible with plastic. New mudguards, seat base (home made out of GRP) and a three into one exhaust system helped to reduce the stock 520lbs to under 500lbs.

That exhaust system was a bundle of trouble. It only cost £25 from a breaker, but it ruined the carburation. All low speed power (and there's normally quite a lot) disappeared. I had a two thousand rev powerband when the bike went like shit off a shovel. After trying different jets I had to give up and revert to the standard three into four system, which worked well despite numerous rust holes and partially blown baffles.

Fuel consumption was a little frightening, it gave 30mpg however I rode and as I often did 500 miles or so in a week this was a very expensive habit. Despite riding quite hard, not bothering with the ignition timing (no strobe...) and restricting maintenance to filling up the oil tank, the engine has given no trouble in eight thousand miles of ownership (it had thirty grand on the clock when I became the owner). The previous owner reckons he hasn't stripped the engine, so 38000 miles for a two stroke isn't bad going and I feel there's plenty of life left.

If I don't change the spark plugs every three thousand miles it becomes difficult to start and the clutch has started to slip at very high speeds. Because it's only cost me £250 so far, I can ride the thing without worrying over wrecking it. If it does blow up on me in a big way, I'll probably just dump the thing in a ditch and start hunting around for another cheapo Jap hack.

I think the engine's classic material but the rest of the bike isn't much cop. Even with the modified suspension the bike still wallows although I haven't had another tank slapper yet - and in the country I've been burned off by 250 Super Dreams. But there's power to cruise at 100mph, although, again, the riding position is the usual sit up and beg crap.

I've had the footrests and centre stand sparking along the tarmac. Getting too confident I once managed to dig the centre stand into the road, lifting the back wheel off the road - it took my stomach about a week to recover from that one. I've had some rides that were so enjoyable that I'd have liked to do them over again straight away if I could have afforded the petrol. And I've scared myself silly a couple of times and sworn my head off at the bike.

I've seen some silly prices demanded for GT750s, even over a grand. But really, they aren't classics - just cheap hacks.

Brian Reading

Sunday 15 January 2017

Kawasaki GPz550


In October 1985 I purchased a 1983 GPz550 for a mere thousand notes. It was a private sale, the bike having only one owner who had only done ten thousand miles in two years. He also had a complete service record and was far away from the normal GPz owner in being over fifty and, as far as I could ascertain, had never thrashed the bike.

I'd seen seven other machines before purchasing this bike. The others had looked their age and I didn‘t much like the look of their owners. This bike actually looked like it had never seen the downside of the English climate. Unfortunately, this was soon to change as I intended to spend a few months touring around the UK prior to taking the bike to the Continent. In all, I would knock up 22000 miles in little more than nine months.

The bike was kept in the front passage until March, when I'd optimistically assumed that the weather would be fine enough to allow me to do some riding and get used to the bike. My keenness overcame my disbelief that it could rain quite so much at that time of year.

My first impressions of the Kawa were tempered by cold fingers and wet roads. Keeping the engine under six grand meant I had to rush up and down the six speed gearbox to keep the bike running along. At least the clutch and gearbox were light and precise. Revving the engine hard above six grand turned the bike into a different kind of motorcycle. The bright red paintwork and racy reputation were fully justified by the arm straining acceleration and delightful exhaust growl.

But the weather and riding in built up areas meant I rarely ventured beyond six grand for the first month of riding. This had a very pleasing effect of fuel economy, with the bike returning 65mpg.

In April the weather was still poor but I wanted to put some miles on the Kawa. I did my first bit of maintenance, and the only regular servicing I was going to undertake, by changing the engine oil. The ignition is electronic and the valvegear bucket and shim, the camchain tensioner automatic and four carbs tend to stay in balance; thus I figured that I could get away with just changing the engine oil every 2000 miles, working on the basis that If the bike was running well, it was best to leave well alone.

In April, then, I went from London to Lincoln the slow way. Once past Luton there are any number of amusing minor roads that avoid the tedious A1. This circular route extends the journey from 150 to 250 miles. I eventually pass just on the outskirts of Cambridge heading for the long, fast and flat roads of the Fens. The freezing winds blow in from the sea over deserted landscapes. I wonder what I'd do if the Kawa expired in the middle of nowhere. There are no hedgerows and nowhere for the pigs to hide, so there are places where I can run the Kawa flat out in fifth with 120mph on the clock. There's a slight weave but it doesn't get any worse so I just have to live with it.

The rumour is that a better rear shock makes the rear end more stable, but the stock Unitrack isn't bad enough to make the effort worthwhile. I stopped in Wisbech - a surprisingly quaint town - to eat some lunch and drink some; warm tea. It really is cold out there, but the Kawa seems to thrive on it. It purrs along even flat out with hardly any harsh vibration getting through. Ridden hard the mpg dips to 52mpg, but I usually average around 60mpg. With a who engine and 125mph bike this is quite impressive.

I followed the A17 towards Sleaford for a while, but take some more back roads before coming out on the A15 a few miles before Lincoln. These back roads have some hairpin bends and small hills. The Kawa can be braked, flicked through the gears or twisted lnto a new direction while in the bends with no problems. The back end squirms a little and the front forks can dive rather violently, but the basic double cradle frame is rigid enough to compensate.

In third or fourth, whacking open the throttle makes the Kawa shift like a much bigger machine; it's great fun playing with the gearbox to keep the engine skirting the redline. The entrance to Lincoln was, as usual, slowed by road works, but the Kawa only weighs 430lbs and it's easy to chuck through the traffic.

I had a friend in Lincoln, so I could stay the night and recover from the cold. Early the next morning, I had to be in work so I took the A15 until it met the A1. These roads are fast and empty that early, but there are many spots on the A1 where the police wait for speeding traffic, so a little care is needed. These lazy A roads are a piece of cake for the Kawa, all I had to do was hang onto the bars, flicking between fifth and sixth, repeating to myself that I was warm. But I can't fool my mind into such beliefs.

As the weather gradually improved I began to use the Kawa to travel further and further out of London, until I was regularly dolng 1000 miles over the weekends. The more I used the blke, the more I became Impressed with the apparent toughness of the engine. It started first press of the button with just a little choke and from there on it just ran and ran. There was just nothing to spoil the Kawa's performance.

After five thousand miles I fitted a new chain. This was one of the cheapo jobs (fourteen notes) and it only lasted for eight thousand miles even though I sprayed it with chain oil after each long ride. The bike was also using a Road Runner every 7500 miles on the rear, although the front went for over ten grand. Two sets of disc pads were needed every 8000 miles. This meant I was spending about eighty quid on consumables every eight thousand miles. In view of the fact that, apart from oil changes, I wouldn't spend a penny on the engine, this worked out as quite reasonable. To go up to the next stage in performance would probably drastically increase these costs, and as I was quite happy with the GPz's performance there seemed little reason to incur such excessive costs.

By the end of May I was ready to quit both my job and England, spending the rest of the year wandering around Europe in the search for some way of making some decent money. I took the ferry from Dover to Ostend. There was only one other bike aboard, a dubious looking Commando. When I caught up with its owner in the bar - recognizable by a tatty leather jacket with a huge Norton symbol on the back - it turned out to be sometime contributor to the Used Motorcycle Guide, Johnny Malone, who spent most of the journey reading out excerpts from the first issue. I wasn't surprised to learn that the editor had temporarily relocated himself in Bangkok to avoid any physical retribution or libel writs after hearing his comments on some of the bikes (I deny this... Ed).



For the first time in what had seemed years, the sun was actually shining. Welcome to Ostend. The Belgian customs just waved us through and I had problems keeping up with the Norton. We were both heading for Antwerp and it had seemed a good idea to follow Malone as he knew the way. Readers of the second issue will know that the Norton is very highly tuned. I had to ride on the throttle and brakes, shooting up and down the gearbox to keep the Norton in sight, although it made enough noise to be heard several miles away. Out on the Belgian motorway I could relax a little, except with the speedo between 110 and 130mph for most of the journey I was afraid the police might stop us. Most of the Belgian police drive around in VW vans which can be ignored, but some of the traffic cops have Porsche 911s which are a different matter...

Following Malone off the motorway, I almost went up a road on the wrong side, but just saved myself. Why we had turned off into thee; countryside escaped me, and so did Malone as the road turned twisty. There was no way I would lean the Kawa over that far... Lost in the Belgian countryside, all I could do was follow the sun. The countryside was flat and desolate just like the Fens. l eventually made it into some kind of stretched out suburb, where small weirdly designed villas littered the sides of the road. A signpost for Antwerp, 20 kilometres, gave me fresh hope.

The drivers in Antwerp were all insane, in urgent need of psychiatric treatment. It came as no surprise to learn that it was only recently the Belgians had introduced the driving test... I liked Antwerp enough to stay there for a few months, very underrated with cheap beer and cheap accommodation. I used it as a base to ride to Germany, France and Holland.

Having little foreign language ability didn't prove a problem and riding the Kawa proved a useful way of meeting people as other motorcyclists seemed keen to talk to foreigners. I eventually caught up with Malone, who was heading back to the UK as he had run out of money. The collapse of the pound didn't help. I'd got a job, cash in hand, in an English owned bar. It meant working from eight in the evening to two in the morning but I got used to that after a week or so. This wasn't going to make me rich but it kept my capital intact.

The Kawa had burned out a battery, but I hoped it was just age and not the electrics playing up. It was beginning to look a little tatty, with rust on the frame and the black engine paint was worn away in places. Rust was beginning to eat holes in the silencers. I'd put eighteen grand on the bike and in a fit of extravagance let the local Kawasaki dealer give it a full service. He didn't mind me hanging around and I was only disappointed in that the valves still didn't need adjusting despite their neglect. It only cost thirty five quid, so I couldn't really complain as it included a steam clean. I touched up the paint and promised myself to clean it at least once a week.

On the radio I kept hearing about floods and cold temperatures, but in Antwerp the sun was always shining and I thought, poor old England. When I decided to leave for Spain, it was with a heavy heart and some trepidation.


For various reasons, I'd better not go into, the journey to Spain has become blurred in my memory. I can remember some custom officials poking at the Kawa and looking at my documents as if they were forged or something... my first impressions of Spain were bad and they just got worse and worse. The people were noisy and arrogant, and some of the young kids were violent. 

Coming out of a cafe, some youth was poking at the ignition switch with a long screwdriver. When he saw me he didn't run off but started to threaten me with the screwdriver. Only the arrival of the cafe owner saved me from getting cut up... the roads were bumpy and after fifty miles the rear shock overheated, lost damping and let the rear wheel lose control. The petrol was lousy, ruining the low speed running of the engine, the accommodation was cheap but full of bugs and I couldn't sleep because I thought someone might pinch the Kawa.

Spain I didn't like and I didn't hang around for long. After three days I turned around, heading back for civilization. This is probably unfair to Spain, but I never met anyone I thought I would care to pass more than a few minutes with. Perhaps if I could speak Spanish things would have been different...

I'm writing this in Paris. The hotel's run by an Algerian and I think there's a brothel in the basement, but no-one seems to give a damn. The Kawa's safely parked in the back alley. I've just cleaned it and it looks like new. I'd like to keep it for a hundred grand. I'll have to think of some far away place to go, but I think the Kawa will survive it...

Alan Smith

Wednesday 11 January 2017

Honda CBX750


As originators and long time advocates of the in-line four, Honda must be wondering just what hit them, as they gradually faded out of the big bike ballgame from the late seventies onwards.

Suzuki captured the market in reliability and Kawasaki took on the heavy performance mantle leaving Honda with nowhere to go but down and out. While the K2 series gave a useful boost in power, they were also heavy, ponderous and somewhat lacking in the reliability that was the hallmark of the original, late sixties, K series bikes.

When Honda finally got their act together by launching the CBX in '83, it was, in many ways, just too late. The CBX was burdened with Honda's reputation for self-destruction gained by their vee fours and a history of making each new foUr inferior to its predecessor.

This is all rather fortunate for potential purchasers of the CBX because its lack of popularity has forced down new prices, and, in turn, left used prices seriously depressed. An '83 model can be picked up privately for not much more than a grand. For such money the CBX offers a lot of serious motorcycle.

The engine is a clear evolution of the original four. There are some definite areas of improvement and some areas that may cause concern to the long term owners.

The DOHC head is quite a neat design with each of the valves having its own camshaft lobe and rocker. The rockers are balanced between valve and a hydraulically controlled piston, that makes setting valve clearances unnecessary. I have my doubts about such a system, but as some engines have done over fifty grand without any apparent problems I can't really complain.

Some camshafts lobes are quite heavily scored by thirty grand, but this is rare, while camshaft bearings don't seem to suffer even if the bike doesn't get its regular three thousand mile oil change.

A hyvoid chain from the centre of the crankshaft drives the camshafts. The tensioner is automatic and despite looking dangerously similar to the one used in the vee four actually works quite well. A couple of bikes need a new camchain by around forty grand but I've heard bikes with fifty grand on the clock that still sound quite quiet. So Honda seemed to have sorted out this problem on the CBX.

The crankshaft has a straight out gear machined into the web for primary drive. This is situated inboard of the left hand outer piston. I would have preferred it on the end of the crankshaft where it was more insulated from the shock of the piston moving up and down, but GS Suzukis use the same setup with no problems so I'll just have to accept it. The gear mates with a weird and wonderful clutch. The clutch has a split gear that in theory takes up any backlash in the primary drive, but in reality will tend to develop excessive wear as the machine ages making the transmission both jerky and noisy. As Honda were able to machine their engine cases with sufficient precision to use proper straight cut gears as long ago as the early sixties I find this incomprehensible.

The clutch also boasts an equally dubious mechanism that lets it slip if engine and road speeds are mismatched on down changes. The other nasty is an alternator rotating at twice engine speed. The alternator has been removed from the end of the crankshaft and resituated under the carbs. Honda, who are famous for making engines with quick wear chains, have tempted fate by running the alternator using chain from the centre of the crankshaft. Lack of a crankshaft-mounted alternator meansthe engine is narrower and the alternator runs in a more pleasant enviroment.

Electronic ignition, run off the end of the crankshaft, completes the picture of an engine that needs minimal maintenance - just a regular oil change and the occasional carb balance.

Honda seemed to have catered to all the areas that are regularly neglected by lazy ageing juvenile delinquents like myself. Even the alternator is not known to fly apart, although the hydraulic clutch does get a bit ratty with twenty five grand on the clock - which serves Honda right for using such a complex design where conventional multi-plate (and non-hydraulic) clutches have proved perfectly adequate in the past.

I've taken so much trouble to define the Honda's engine because it is a relatively unknown quantity on the used market and rather under estimated in terms of usefulness and longevity.

The engine is stuck in a fairly conventional twin down tube frame that uses the frame tube to contain engine oil. All of the 750 fours have had separate oil tanks, so this is nothing new. Dumping the oil tank might go some way to helping keep the mass down to 480lbs, but it's probably more a product of losing weight inside the engine and using plastic on the chassis wherever possible.

The half fairing is neatly moulded into the petrol tank giving the bike an integrated appearance from head to stop lamp that's far ahead of their previous efforts - and even looks quite neat up agalst their fully faired high tech vee fours.

The rider sits in the CBX with a nice chunk of five gallon fuel tank to grip with his knees, handlebars that don't immediately strain the back or wrists and a mildly stated array of instruments held in the fairing. The clutch is light and just looking at the throttle gets the rev counter in the red. First gear engages without any of the usual Honda noise and the bike will move off on the minimum of throttle.

it doesn't exactly go screaming off into the distance, in developing so much power from a mere 750cc Honda have concentrated on delivering most of the go above seven and a half grand. The bike's quite happy at lower revs it just doesn't deliver very many kicks. There's a little surge beyond 4500rpm, but hit 7000 and everything begins to happen very quickly, the silencers make a nasty snarl and the arm stretch effect is quite disturbing.

With six speeds to play with I would have been happy with four - there's many different ways that the Honda can be used. Stick the thing in sixth, and it'll potter along up to about 90mph, when the power will suddenly kick in and get the speedo around to 125mph with no trouble. True top speed works out at about 130mph, but that needs the bike screamed in third, fourth and fifth to obtain the last 5mph. The fairing provides sufficient protection to make 100mph cruising quite pleasant, although wet weather will still penetrate gloves and jacket. It's a lot better than a bare bike.

The suspension is complex but tends to work quite well. The strong front forks are burdened with something called TRAC, which I won't even bother to write out in full. Anti-dive is operated by the calipers on the twin discs in a manner that avoids rational comprehension and, as it doesn't seem to have much effect, can best be ignored.

Alr can be pumped into the forks to improve the springing, although standard settings were fine for my ten stone. Damping is also adjustable, .but with twenty grand needs to be on the firm setting. Rear shock is controlled by Pro-Link. The shock is hidden away but damping is remote controlled via a cable and springing by pumping in air.

This is all rather clever but let down after fifteen grand by the shock which loses most of its damping and a swinging arm that wears at the bearing points. It says much for the integrity of the frame that it still refuses to indulge in speed wobbles.

The combination of weight distribution and steering geometry that the Honda uses means that it feels easy to throw around in traffic and, yet, doesn't get vague at high speeds. Much of this is down to the excellence of the riding position, with footrests placed well back, flat bars and a comfortably shaped seat. The rider feels at home on the bike straight away.

I had the opportunity to swap straight from a CBX to a 1970 CB750, and the difference in feel was quite extraordinary. The two bikes really are decades apart. The CB felt loose, sloppy and imprecise, it needed so much more muscle to ride and the engine felt flat, like someone had switched off two cylinders.

Out on some fast country roads there was no way even a suicide artist could hope to keep up with the CBX on one of the older fours. The CBX still weighed too much and that mass could still catch it out if you tried to change direction too violently on bumpy curves, when the bike would tend to go too far towards the new direction, and a series of small lurches would result. On the CB750 the same kind of action would have the handlebars dancing and the bike lurching off towards the wrong side of the road. On the CBX you can brake, shut the throttle or wave to young ladies while banked over without any problems.

I particularly liked riding the CBX in the rain. There was enough bodywork to give moderate protection to hands, knees and shoulders; the Honda could be used safely in the mild half of the rev range and I never had to worry over the tyres doing something unexpected. The only mild worry was the brakes, which while powerful and, usually sensitive, would occasionally lock the front wheel without any warning. I can only assume that somewhere along the line the antidive was interfering with the efficiency of the units. The rear disc was no better than any number of drum brakes I've used...

In the dry, the twin discs had loads of power, using the CB750's single disc was dangerous in comparison because I'd become used to leaving my braking to the last possible moment and the older four was more likely to go straight through something than stop by the time I'd realised my mistake.

Brake pad wear is not amusing, 7500 miles from either front or rear means three sets of pads at £12.50 a pair. Fuel economy was rather good for the available performance. Keeping below 7500rpm gave an average of 55mpg, with a bike still able to break through the speed limits.

Using all the available power, having the maximum amount of fun, meant economy went down to just over hOmpg, but to get down to this level required some pretty wild riding that would soon be halted by loss of driving licence. Heavy 100mph cruising returned 45mpg and the bike averaged out at 50mpg.

The rear tyre was worn out after 7000 miles and the front after 12000 miles, which in the high performance league isn't bad going. Front tyre is a sixteen inch job, which except for being very expensive to replace, has none of the twitchy nature of some of the wheels of that size on other bikes (who mentioned Suzuki?).

As 750 straight fours go, the Honda comes out leading the pack in the handling stakes. It has the same kind of stability as the old GS range but with much quicker and easier steering, that belies the fact it weighs so much. There is a slight top heavy feeling on first acquaintance with the bike, but this is soon forgotten.

That the handling abilities are exceptional for a Jap bike is quite true, but some kind of true perspective can be thrown in here, by comparing the CBX with either Dresda or Rickman-framed CB750s. Both of these bikes are lighter, just as stable but not quite so quick steering in curves. The comparison is a little unfair as neither of the specials have to cope with the sudden application of power at 7500rpm. I guess that if the old CB had the kind of handling abilities as the CBX the specials would not have sold very many frame kits.

Using a bike with a worn swinging arm, a shot shock, tyres just down to the legal limit and fifty grand on the clock was an interesting comparison with the low mileage bike I'd been riding. The bike was very sensitive to white lines and the back wheel could lose traction over bumpy curves, but the frame;was basically sound enough to take it all in its stride. When the laziness of the local council left a foot deep crater in the road, the Honda twitched the front forks for an instant and then settled down. The rear shocks gave me quite a kick, but at least my body was ideally positioned to absorb most, of its force. This kind of stability out on the edge of suspension, component and tyre wear is very encouraging.

The motor still knocked out that delightful surge of power, but low speed running was a little troubled by carb problems, probably resulting from the owners reluctance to change the air filter. The engine sounded fine, the clutch was a little remote and a little jerky, but nothing a few miles riding couldn't absorb. Problems seem to vary from bike to bike, with no discernible pattern. Some rectifiers have burnt out, some cams worn out, some clutches started slipping, but there seem few instances of the engine blowing up. In the States, where the bike is much more popular, tuned engines haven't led to instant demise.

The silencers last three years and it's a brave owner who opts for non-standard replacements (carb problems become very amusing). The black engine cases lose their shine after two English winters. The paintwork is good for a lot longer and comes up real nice with a bit of elbow grease.

I forgot to mention vibration for the fairly simple reason that I never noticed any.

In performance terms (speed and handling) the CBX is easily the best four that Honda have ever built. It makes the CB750 look like an antique. So far, the motor has stood the test of neglect and crazed right wrists as well as any other big four, whether examples will clock up 100000 miles like the original is another question. I have the feeling that when the over complex components that make up the CBX's engine do fall they will do so in a very expensive manner and a big way. When that occurs is anyone's guess, but I wouldn't be happy buying a bike with more than twenty five grand on the clock.

Nice one, Honda.

Bill Fowler

Wednesday 4 January 2017

Yamaha XZ550

When the V50 finally got the shove, it was due more to panic than to choice.. Rotting electrics, naff oil pump and blown seals in the front Brembos, were the final straw in a 12 month catalogue of disasters and rebuilds.

In my panic I replaced the Guzzi with a 1983 Yamaha XZ550... Yes, I know what people say about the thing, but it only had 7 grand on the clock, and apart from dented silencers (scrapyard specials), it was in perfect nick. So, in December '85 the Guzzi went to a new home.

Now, inherently, the XZ550 ain't as bad as everyone makes out. I actually quite like the angular styling and the way the water-cooled Vee twin nestled in the frame. The motor was quite responsive with none of the flat spots I'd been led to expect. Also there was very little vibration, right up to an indicated 120mph.

However, for a claimed 65hp, there seemed to be very few of them at the bottom and middle of the rev range. Keeping the electronic rev counter above six grand made the bike quite capable of making street racers look rather stupid, and even gives the odd exotic sports car a shock.

Being water-cooled appeared to help out the economy, somewhat. It was far lighter on the wallet than the Guzzi, giving anything up to 70mpg under gentle use. This could drop to around 35mpg when two-up at a ton motorway  cruising.

It would normally start first prod when cold, but could be very temperamental,and would sometimes only start after getting . the throttle/choke combination absolutely perfect. When it was running, the engine was extremely quiet, and even the pipes only let out a muted purr. That was soon, er, solved with a hammer and a punch. Well, I like to know I've got an engine there...

The engine is a home mechanic's nightmare. Almost every bit of maintenance requires removal of the engine from the frame. About all that can be done with the 3 motor in situ is change the oil. Even changing the plugs requires the patience of a Zen master.

The gearbox was a strange paradox. The clutch was very light and direct, but the gearbox was very clunky. Clutchless changes were smoother than using the clutch.

Handling? Well, that was extremely indifferent. Never razor sharp, nor totally heart stopping. Just boring. The front end was too soggy and let down the De-Carbon monoshock which could cope with high speed lunacy and the occasional two up off road ramble (don't laugh, I was following a similarly laden 750 Bonnie!).

Overall, it coped with bends and straights with equal competence. However, when the tyres (Avon Road Runners in this case) became worn, high speed weaves didn't inspire too much confidence. Nothing terminal, just a little worrying.

On the other hand, wet weather riding was a little more disturbing. Road Runners that were normally pretty competent on other machines were rendered useless when leant into curves — the back end could step out with no warning at all. The twin front discs had more than enough bite to stop the XZ from any sort of speed. In contrast the rear drum had very little feel or accuracy. But, overall, the bike could be stopped without any problems , at all. The general finish of the, bike, was excellent. A deep lustre silver grey tank and side panels, good paintwork (ie no rust) on the frame and chrome that still shone after three British winters.

The seat was comfortable up to about 170 miles, which usually coincided with refilling the 3.7 gal tank. Mirrors only blurred at illegal speeds, which didn't make much difference, anyway, because they only gave a view of the rider's shoulders. Stands were both easy to use and never let the machine fall over. Lights were powerful and all the controls were both accurate and easy to use.

So far it doesn't sound like the bike often described as disastrous, does it? That's because I haven't mentioned the XZ's main problem - reliability. Basically, it doesn't have any!!

The first problem occurred with 10500 miles on the clock. It blew all six engine gaskets, dripping coolant down the barrels (removing all the lacquer), and letting oil into the cooling system. New gaskets cost £60. At the same time the fork seals went - £8 a pair.

Now being disinclined (and lacking the tools) to heave the lump out myself, it went to a dealer. Four days and £130 later it was returned with an air lock in the cooling system, and fuel spraying out of the carb breather. It was fixed by the dealer but never ran properly afterwards (no names, no libel writs...).

Next problem came from the electrics. The battery packed up, the starter solenoid shorted out and flattened the new battery; the regulator/rectifier unit burnt out, which also finished off the alternator. All but the alternator were replaced (even getting the old one out was now beyond my finances). Finally, when one of the exhaust valves in the rear pot burnt, out, I decided to get rid of it.

So, after eight months of ownership and putting another ten and a half grand on the clock, it had gone through two rear tyres, one front tyre, a whole set of gaskets,a pair of fork seals, one pair of brake pads, a battery and various other electrical bits, plus all the usual oil, petrol, filters, etc.

If the bike had been easier to work on (for instance, the carbs were downdraught, further complicated by accelerator pumps and a dozen jets) and 200% more reliable, I might have kept it. However, ridiculous problems, extortionate prices and crazy waiting times for spares (14 weeks on average), eventually made me swap it for an X5650 engined chop. And that's another tale...

S. Wallis


Tuesday 3 January 2017

You too can be a Motorcycling Journalist...


The High Cost of Nostalgia

If it didn't sometimes affect my life, I guess the prices asked for many of the classics could be dismissed as merely amusing. I'm not objecting to the fact that devices like Vincent Vee twins are now so valuable that very few of them are actually used in anger on the road - although their rarity and cost does mean that no-one's willing to let me borrow one to bring you my usual brand of delinquent road test.

Which is probably one of the few ways anyone's likely to find out the truth about those old beasts. The way most classic tests are written is as bad as those sixties style road tests that so helped the British industry to self destruct — so scared were the magazines of offending the manufacturers and losing advertising in those days that they didn't even dream of reporting on the reality of some awful machine. The impetus of these old tests, mixed with a bit of patriotism and fuelled by the present profoundly dishonest classic scene has seen all sorts of awful devices promoted as both useful and classic machines.

As I have as little as possible to do with this scene (having neither the money to waste nor the time to keep on checking bolts, tappets and anything not welded firmly to the frame), I could normally ignore it with impunity, with the occasional bout of hysterical laughter thrown in, just to keep a sense of perspective.

Unfortunately, the same mixture of blind faith and disturbing ignorance are beginning to make their insidious way into the used Jap camp. Of course, the forces are nowhere near as strong — I mean it's relatively easy to become absorbed by some old brute of a British bike, given that they often look so right and it's one of the few ways left of waving the Union Jack. When magazine writers, and even the occasional punter, begin to shout the joys of certain old Jap bikes, I can only wonder if we live in the same world and ride the same bikes.

I appreciate Jap bikes because they have engines that can often be neglected and thrashed without any ill effects, and because some of these engines in certain rolling stock can produce great thrills on the road at a cost that doesn't burn huge holes in my bank account. If the price of these bikes were to rise to the heights of the British stuff, then I would rapidly lose interest.

A lot of the old Jap bikes are really terrible devices that do not even have reliable engines to mitigate against flimsy frames, soggy suspension and unreliable brakes. If anything goes wrong with them, spares are often either horrendously expensive or difficult to find.

Regulars readers will be finding this difficult to follow, as most of the space in this magazine has been devoted to used Jap bikes, promoting them, for most of the time, as a cheap way of getting some fast but inexpensive kicks on these increasingly dreary roads. But that's just the point — it's still possible to pick up a used Jap bike for a couple of hundred quid that has a reliable engine and enough power to make life interesting.

Let too many idiots write too many articles that fail to mention the downside of so many Jap bikes and we end up with a market that starts to inflate prices and fails to differentiate between the good and the bad. While there are a few old Japs that do merit classic status - either because they started a new trend or performed so well that they can't be ignored, there's a whole genre that has only one point in life to provide excitlng transport on the minimum of money.

It's bad enough having highly dubious Wop bikes costing the earth, if the same process begins to afflict the Japs, we may as well give up and start figuring how to get enough cash together to abscond to Bangkok.

Luckily, in this one sense only, the UK is still deep in recession; the market forces that could wreck the used bike scene for the private punter can't really get going. It'll be amusing to watch the established magazines as they try to latch onto the used Jap market, because their editorial policies are more or less determined by the amount of advertising they can generate, so their coverage is going to be slight until the prices of used bikes become high enough for the dealers to afford the adverts, but the market won't respond until the coverage increases...

Bill Fowler

Sunday 1 January 2017

The Good Trail Bike Guide


In the early seventies when the first trail bikes began to make any real impact on the motorcycling public, they were basically road bikes with knobbly tyres and high handlebars thrown on to make them look the business. These tyres were often made from such a tough rubber that they outlasted the engine, but along with tiny SLS drum front brakes made fast riding on tarmac fraught with danger.

On the rough, the useless suspension, the questionable steering geometry and often ill conceived weight distribution, meant that the bikes would bounce around and throw the rider off with all the ease of an angry horse, unless the rider was highly skilled or very lucky. That any were sold at all, and most were used on the road, was down to their raunchy looks, cheapness and a certain degree of fun inherent in lightweight two stroke singles.

Predominant in this ballgame were Suzuki and Yamaha. Right at the beginning of the decade Suzuki were leading the way with the TC120 Trail Cat, a device that used a 120cc 2-stroke engine with a four speed box that could be turned from road to trail ratios at the flick of a lever, giving an effective eight speed box.

Like the later TS range, the engine was quite tough but could quite easily blow its main bearings or seize up. A straightforward engine design, it was easy enough to strip down and rebuild, but the bike is so rare now that you’re very unlikely to find a good ’un.


Of the TS range the TS250 stood out as their most useful device, although neither the 125 nor 185 versions should be easily dismissed. The 250 was introduced in 1973 and made it to 78 without any major changes. Subsequent models had dodgy engines, although the chassis was actually quite useful for green laning. It was the best looking of all the trail bikes in early editions.

Handling on the road was a little queasy above 50mph, with the trail tyre stepping out on wet corners with rather too much ease and many were the youngsters who were rewarded with a dose of gravel rash from an overdose of throttle.

The motor reached its development climax between 1977 and ’78 when it’d take the TS to 75mph and return 65mpg. Running costs were minimal, save for swinging arm bearings that lasted 6000 miles, chains that went in 7500 miles and a disturbing penchant for blowing light bulbs with amusing frequency.

Engine life goes from between 15 to 25000 miles before needing a comprehensive rebuild. But the 250 was tougher than either the 185 or 125 that could blow up with less than ten grand on the clock.

Off road riding was good for a laugh. You sort of have to hang off the back of the seat to make it wheelie at speed, and it liked to land on the front wheel and cartwheel bike and rider into the rough stuff.

Prices for any of the TS bikes vary enormously and their condition is so removed from their age, given that you could ruin one in a month’s hard trail riding, that you can only go to have a look at one and see what it runs like. Try anywhere between £50 and £275.

Slightly more useful off road, but not so pretty, the Yamaha DT range sold by the boat load in the seventies. Available in 125, 175 and 250 versions, the DT 175 was universally acknowledged as the best of the bunch, having the most usable combination of mass, power and toughness.

Introduced in 1973, as an update to the not dissimilar CT2, this 171cc 2- stroke managed 16hp, 70mph and 60mpg. The reed valve engine had a wider spread of power than the TS, whilst the frame was tougher, the suspension little better but the geometry more useful and the bike less prone to nose diving on the rough.



On the road the handling was no better than the TS, although it was slightly less easy to fall off. Thrash the poor old thing hard on the road and the engine will blow up, with a certain penchant for blowing crankcase seals and/or burning holes in pistons.

The tiny front brake was probably the worst of all the trail bikes, with terminal brake fade and quick wear pads. Chains lasted a little longer than the TS, tyres a little less and the electrics were more reliable.

Both the 125 and 250 versions are no worse road bikes, although the former is a little peaky and tends to be thrashed, whilst the latter vibrates enough to put most of the sex shops out of business.

Ever a little ahead of the game, Yamaha got serious for the eighties by fitting the DT out with monoshock - although the bike was useful in the dirt it wasn’t so versatile as the older bikes on the street. Prices are, again, unrelated to age, but as a road bike it’s perhaps best to avoid the 175 as this was the most popular bike for off road abuse. Anything from £50 to £450 depending entirely on condition.

Kawasaki were always much less obvious in the sales stakes, their bikes usually defined as being too heavy but more reliable than their rivals. The KE series didn’t hit the streets until the mid seventies and the 125 and 175 had some of the style of the Suzuki, but were the slowest of the bunch. Of these two the 175 is the one to go for, weighing only twenty pounds extra and having quite a bit more go.

A little later Kawasaki introduced a 250 version which made 22hp and weighed in at 2751bs. This didn’t prove to be very reliable, something to do with the crankshaft writing itself off due to lubrication problems and handled like both tyres were deflated on the road.  All of these seventies Kawas are very rare, so you’ll have great difficulty finding one, but expect to pay between £50 and £250.

Honda initially kept well clear of the two stroke camp, concentrating on their XL250. This single cylinder four stroke was both overweight and underpowered in comparison with the strokers. Like the older British four strokes, the engine was not entirely reliable, liking to eat camshafts, tensioners and camchains, not to mention the odd piston and complete gearbox. To compound the problems of the XL, it didn’t deliver bags of low down torque and would shake merrily away under hard use.

Off road it was a complete slug, especially in its early form (’73-'76), when the tendency to go straight through rather than jump over obstacles doubtless helped explain the ease with which the frame could, er, break.

On the tarmac, with 20 horses to shift 300lbs, things were a little more enjoyable, although the limitations of tyres, brakes and suspension were all too apparent beyond 55mph, when the beast would waggle and wobble if you were foolish enough to try to lean it over more than a few degrees or became at all violent in your cornering techniques.

The front brake was one of the better fitted to these aged trail bikes, fuel could be quite reasonable at around 60 to 70mpg and with a bit of attention to detail (like fitting a different set of forks and wheels) it could make a useful road bike. Prices go from £50 to £200.

Rather more usable off road was the four valve head version introduced in ’78. The XL250S boasted a large front wheel, a few less pounds and despite claiming no more power than the earlier bikes was good for nearly 80mph, but only in a straight line, please.

The engine is not dissimilar to the RS250, with the same chain driven balance weights and the same self destruct urges. The S also boasted an awful gearbox that needed the kind of boot pressure leading to quick wear booties and a twin port exhaust system that were out just after the warranty expired. It’s difficult to work out if the XL250 is better or worse than the XL250S, both have their problems and are little longer lasting that rival strokers. Don’t pay more than £300 for an S.

The replacement for the S was the XL250R, a similar engine with a mono-shock rear suspension set up, that like later Yamahas was a much more serious off road bike than earlier efforts and therefore of little interest to street poseurs.

Honda were rivalled in the four stroke camp by Kawasaki, whose KL250 hit the streets in ’78, and like the early XLs was a bit of a laugh off road but quite useful for tarmac burning. The engine was nicely straightforward and produced rather more low down power than the Honda. It could gently coast up to 75mph, but would return as much as 7Smpg. Brakes were dodgy, handling soggy and there was far too much mass on the front tyre for off road rambling.



Probably the least useful of the off roaders, it has its uses as a cheap commuter or hack. Updated until ’83, it gradually became more usable off road. Prices go from £75 to around £750 for the latest stuff. Engines are the most reliable of the trail bikes, only prone to rapid piston wear if you forget to change the oil.

Beyond 250cc, the territory is taken over by the four stroke singles. First amongst these was the XT500, a device quite famous for refusing to start at the most awkward of moments and for throwing off riders with less skill than world champion scramblers.

The SOHC single cvlinder engine looked just right, but was spoilt by poor low speed pick-up and a dodgy gearbox selector. Although 30hp wasn’t all that much to write home about, it was more than enough for the chassis to cope with off road, the speed and mass would turn the world upside down very rapidly.

Piston wear and valvegear wreckage are not uncommon on hard used bikes. Top speed on the road is around 90mph, whilst fuel comes in somewhere between 40 and 60mpg. It does eat up chains, swinging arm bearings and front drum pads quite rapidly.

The 500 was updated to the XT550 with a four valve head and a twin choke carb to give improved low speed torque for a faster getaway, and, despite the use of a balance shaft in the engine, it was both faster and more economical than the 500. Beware of the weak clutch and rapid wear of the mono-shock suspension components.

In 1584 the XT600 took over, combining a front disc brake and improved rear suspension to make it the most usable of the big singles, although the reliability of the engine isn’t quite all it should be due to poor piston rings. Prices for the big Yamahas start as low as £200 for an XT500, £350 for an XT550 and well over a grand for the 600.

Honda’s 500 was never as inspiring as the Yamaha, although emerging a few years later it had the time to develop a more civilised motor and off road habits. Early versions are quite rare, and like the later mono-Shockers, not helped by the way it eats cams. Prices from £350 to £750.

The Suzuki SP370/400 was often thought of as the best off roader with a better combination of mass and power than most 2505 or 500s. It can have a dodgy top-end and breaks the kickstart gear, but otherwise a fine little roadster and quite usable off road. The 370 was faster and more economical, the 400 slightly more reliable. These are very rare nowadays but worth the effort of hunting down.

Of recent times, only the Yam XT350 stands out as offering anything like the older bikes combination of fun and practicality, but this device had such appalling styling that its appeal to road riders is strictly limited and like the XT125 and XT250, they suffer from cam problems if thrashed.

But forget post ’80 stuff, for the most part they have lost the elements that made the seventies bike so much more fun to ride. There are loads of Italian bikes and rarer Jap beasts that haven't been mentioned because they are so scarce and/or unreliable.

Although the earlier bikes were both hopeless off road and dubious on the tarmac, they were (and still are used) cheap and cheerful fun that also just happened to look a little flash. You just can’t get that kind of deal these days. It’s also quite easy to update them with suspension and brakes to make them better road bikes.

Al Culler