Friday 13 December 2019

Yamaha XS1100 v Kawasaki GPz900


The state of the secondhand market over the past couple of years has been well weird. Some will insist that prices are rising fast as fewer and fewer new bike sales means that good used bikes are becoming very rare. Others suggest that because the cost of running anything bigger than 100cc is so horrendous (insurance, tyres, chains, fuel, servicing, etc. etc.) that more and more people are giving up on motorcycling in disgust. Either a bicycle or used car taking the place of their motorcycling dreams.

Then there’s the classic mob who so effectively ruined the British bike scene. Before the Great Depression took over, prices of some Japanese bikes were trying to assume classic proportions, although in reality, even back then, shifting some seventies or sixties Japanese iron at a high price was extremely hard going. These days it’s just about impossible to sell old Japanese bikes for much money.

Which is where my XS1100 came in. I purchased this beast six months ago. A 1980 item with 22000 miles done, it was a bit tatty with the electrics in a very sad state (no working lights or horn, etc). I'd owned one of these brutes when they first came out, so knew what to expect, having done 30000 miles of high speed madness and survived to tell the tale. When some bozos had started talking up the dear old XS as some kind of classic, the last of the breed and all that crap, I wanted to tear the offending magazine in half. Pah! Some people demand thousands for them, I bought mine for a mere £450!

Even then it was a bit of a self indulgence as I had a perfectly good Kawasaki GPz900 sitting in the garage. This road warrior was superior in almost every respect to the XS1100, save that it lacked the low speed grunt with which the Yamaha was endowed - the bloody great beast could be rolled off with a whiff of throttle from third gear if you had a mind to, despite the fact that it weighed nearer 600 than 500Ibs!
 

It took a long weekend to sort out the XS1100. As this was the depth of winter I was thankful for my central heated workshop/garage (having built an extension to the house for a kitchen which just happened to abut the garage, so I managed to slip in a radiator before the wife had time to complain). The wiring was all rotted, the handlebars switches were shot but, luckily, the rectifier and alternator were still working OK. Shame the same couldn't be said about the corroded black object that I guessed was the battery.

I fitted some switches for the lights, dumped the indicators, used a car ignition switch (which also replaced the starter switch) and fitted a secondhand battery. I touched up the paint where necessary, paid the kid to shine up the chrome and alloy, and popped on an old BSA A10 silencer on to the decayed four into one exhaust system, the original silencer having fallen apart on the ride home. The resulting noise gave the XS an interesting exhaust note, which confused ancients on British iron as much as the plastic missile crowd.

My GPz900 was in pristine shape, having rebuilt it from the frame up, so I intended to use the XS through the worst of the winter and keep the GPz for happier times. The GPz is not a light bike, but its steering is way ahead of the XS, so jumping from one machine to the other could be very disconcerting. As the XS always made its presence felt, I usually got caught out when leaping back on the GPz, either putting too much effort into the steering or throwing myself over the bars when grabbing the front brake lever!
 

Any XS that has been around will have had some essential modifications - tightened up front forks, fork brace and aftermarket shocks - if they haven’t, chances are they have been run off the road, especially after a few years wear gets to the suspension components. Ridden within reasonable limits, an XS thus modified is not that bad a handler - believe it or not! Certainly, shooting around town showed up few problems, the most pertinent being a bit of restraint on the throttle to stop the rear tyre churning itself to bits on take-offs.

Compared to the Kawasaki, you have to be very heavy handed with the controls - massive muscle to change direction and knuckle busting pressure on the front twin discs... the front brake was so unpredictable in the wet that I was almost forced to use the GPz, which would have nullified the whole point of buying the XS. When I took the front calipers out I found that there were no less than four different makes of pads present, all about to go down to the metal. I had to hand over nearly thirty notes for two sets to the local dealer, I could have knocked the smile off the smug, rip-off bastard's face but managed to restrain myself.

With proper pads, the feel of the brake was transformed, although it still needed a grip that would have a gorilla screaming to an animal rights organisation. In the wet there was a moment's lag but enough feedback to stop me locking up the wheel. An acceptable compromise was reached. The clutch was another heavy item which also had a habit of becoming very vicious after ten minutes of overheating in heavy traffic - the last thing I needed was a lurching power take up on a bike so powerful and heavy as the XS, but I eventually grew used to it.

Although I'd rewired the lights they were not very powerful and prone to blowing, so I had to spend a weekend going over all the wiring, adding some rubber mounts to the headlamp and sticking a capacitor across the bulb leads (to take care of any excessive voltage in the system). Not much better, the bulb still blew every 500 miles or so. Unlike the GPz, which had car drivers cowering in obeisance, the main beam was useless for much more than 25mph down dark country lanes. With the precarious state of the electrical system I had no intention of fitting a more powerful bulb and I didn’t think a Halogen set-up could take the vibes.

Apart from these minor quibbles, I've rather enjoyed hustling the big bruiser the 30 miles to work and back for the past six months. There’s a mixture of heavy traffic, a fast bit of dual carriageway and some violent swervery. The traffic is blasted past in first or second gear at maximum revs, the engine making an unholy row which intimidates the cagers out of the way. I occasionally have to brake like mad and haul the bike into a narrow gap between cars when a bus or artic coming towards me refuses to give way. The XS squirms around a little but it’s just a matter of mind over matter to get it to do what you want.

The Yam will still growl up to 130mph on the bit of straight but the degree of secondary vibration is more than off-putting, it’s bloody dangerous. I’ve had the footrest and the headlamp fall off as bolts have rattled loose. I'm old enough to have experienced British bikes and the almost religious expediency of having to tighten up bolts after each and every ride, but it’s not something I wanted to get into with the Yamaha. Although the XS is never entirely smooth, keeping the beast below 95mph in top gear subdues the vibro massage effect to a level that keeps the plot in one piece.
 

Rather shockingly, the XS is almost as stable at speed on a relatively smooth and straight road as the GPz! The latter shakes its tail between 90 and 120mph before settling down again whereas the XS doesn’t start to weave a little until 115mph is on the clock. Admittedly, the GPz is running stock suspension and if the XS was in a similar state the Yam would be a real pig once past the ton.

On bumpy roads, all the old complaints about heavyweight Japanese fours are present, with lots of jumping about, squirming and wallowing. The GPz is often 20 to 30mph faster through curves than the poor old XS, which can at times be a very frustrating bike to ride - you sit there in restrained agony knowing you've a bucketful of torque and power just a twist of the throttle away but scared shitless to hit on it, knowing that the chassis will throw you off as soon as the going gets tough. The tendency of the bike to run wide through corners does not help in the least.

Sometimes, though, I got in the mood and shed years of restraint and maturity, riding the XS on the throttle and the brakes, cutting a high speed dash through the worst bends the English countryside could throw at us. This involved ramming open the throttle in third or fourth, slamming on the brakes on the wrong side of the road, cutting through corners in the straightest line possible, all the time aware of the way the back tyre was skipping and hopping all over the place, and wondering which way the forks, all twisted up and down on their stops, were going to throw the bike next. It required ace reflexes, a weightlifter’s muscular input and a body full of a massive overdose of adrenalin.

I used to be able to ride like that for hours and hours, these days thirty minutes reduces me to a shaking wreck, the combination of age and easy life (on the GPz) having seen to that. I can do the same kind of speed on the GPz with absurd ease, not needing to turn myself into some kind of wretched, mad, superman. One thing about having these two bikes, if I ever get bored with the sheer civility of the Kawasaki, an hour’s fast riding on the Yamaha soon reveals how lucky I am to have the GPz!

I have few qualms about thrashing the XS, the engine is one tough piece of alloy. The carbs keep going out of balance every 500 miles or so, but proved impossible to balance with a set of gauges... as soon as you started adjusting one it would put the others out. In the end I just gave up, they never seem to go way out. With just over 35000 miles on the clock now, I don’t expect to have to do any serious work for another 50000 miles. In that respect the GPz900 has shown few advantages, despite the added benefit of water cooling.
 

I bought one of the original 1984 GPz900s, two years ago. The engine boasted 58000 miles and was comprehensively worn out but still ran. The chassis was in much better shape as the bike had been a well maintained, garaged, one owner. It even had a shiny stainless steel four into two exhaust. I handed over £1100 for this creature after a lot of haggling, the original owner being rather distraught at the state his engine, which hadn't been thrashed, had reached. He swore he was never going to buy another Kawasaki again.

The engine was very noisy, smoking badly and had a fit of the shakes if I tried to rev beyond 5000rpm. I cautiously rode home, hand hovering over the clutch in case the motor decided to seize up on me. Early 900s had a whole catalogue of faults which included an engine that could run low on coolant without any warning (thus overheating and seizing), a poor oil supply to the cams and a camchain that could rattle with enough agony to impress a CX500 owner. Not to mention the infamous freezing carb affliction.

Dropping the engine was a relatively easy business as the backbone frame meant the chassis could be lifted away from the motor. Evidence of much work on the motor was found in the condition of the cylinder head bolts. One horror after another was revealed cams with great big chunks missing from their lobes, pistons with shagged rings and large score marks, and a crank that rattled on what was left of its plain bearings.

To be honest, I had expected as much and had already located a much newer motor from a breaker, mine for £600. As it was out of a crashed bike with 15000 miles on the clock, I hoped that there would be a lot of longevity left in the unit. Fitting the engine back in the chassis went without incident, it was really a two man job but I managed it on my own. As the tank and panels were rather faded, I handed them over to a mate who stripped and painted them British Racing Green. With a bit of touching up, polishing and tidying I had a £1700 GPZ900 that looked as good as new!

First impressions were not too good. The front wheel flopped into low speed bends, the forks shuddered whenever I so much as touched the front brake and the engine felt gutless at lower revs. Not what I had expected from a hot-shot superbike that had been praised no end in the glossies. Of course, the answer was easy, rev the motor beyond 6500rpm... then the scenery rushed past at an astonishing rate, the handling tightened up and the bike cruised along so solidly that it was dead easy to believe you were just galloping along at the legal limit when in fact you were a lot nearer the ton!

I didn’t like the gear change very much, though, not very precise and it took a while to know when the cogs had actually slid into position. Bopping along on my commuting route at a reasonable pace returned 52mpg, which was about 20mpg better than the XS later managed and as good as many a 250 twin! Hardcore riding could reduce that to around 40mpg, as could cruising along motorways at 120mph, something the bike did with an absurd ease, the combination of riding position and fairing cosseting the rider to a degree than would make a full touring rig Gold Wing owner sit up and take notice!

The only problem with such indulgence was that the Kawa tore through consumables like I had a job with Kawasaki. Tyres were chewed up and finished in 3500 to 4000 miles, the chassis demanding a decent pair of Metzelers with at least 2mm of tread left if suicidal tantrums were to be avoided. The brilliant braking with which the bike was endowed was only made possible by fitting pads of a constitution which was destroyed in 4000 to 5000 miles. An expensive O-ring chain was reduced to a really ragged state after 6000 miles, turning the transmission as crunchy as a twenty year old Honda four’s.

The XS actually proved cheaper to run on consumables. The shaft drive eliminated all the messy and expensive chain business, it would remain stable fitted with a relatively cheap set of Avons that lasted about 6000 miles a pair and the pads lasted well over 10000 miles. Only the fuel, never much better than 35mpg, gave pause for thought. Yes, I know, if I wanted a commuter I could buy a Honda C90 and bore myself to death with tales of its frugality, but I’m not that bloody old!

I've done about 23000 miles on the Kawasaki without any major problems, including a couple of European tours that clocked about 4000 miles a throw. The bike was ideal for blasting down German autobahns at about 140mph, even then the vibes were not too harsh, nothing compared with the buzz that the XS produces at similar revs.
 

On newish tyres stability was fine at that kind of speed, but by the time they were down to about 3mm there’s a slight weave that I just knew would turn into a wobble if I was ever silly enough to run the bike on, say, 1mm of tread. I had to fit a new set of tyres when in Germany, where I was easily won over by the friendly, efficient service from the motorcycle dealer. I’d just rolled up on the GPz and they did the job while I waited, including taking the wheels out themselves. I was even offered a test ride on a ZZR1100 if I wanted to come back the next day. A set of tyres and fitting worked out slightly cheaper than buying ‘em mail order in the UK!
 

After these high speed excursions into Europe my conclusions were that the GPz was a very versatile bike but its potential as a tourer was ruined by the need to keep supplying it with very expensive consumables. Rather than buying another big brute of a four, I should have looked for a 400 to 500 twin which would be cheap to run but still able to lope along at an adequate speed. Such rationality was ruined by the fact that once experienced, the heady rush of acceleration and power of a large four, it’s very hard to settle for anything less!
 

So there you go. I’m quite happy with both my bikes. If times got seriously hard I could live with either. The used market is still in a state of confusion but the bottom line is if you are willing to buy a bike that needs some work there are still plenty of good bargains around. There is also lots of overpriced crap on offer, so, as always, it’s let the buyer beware.

Mike Donaldson