Buyers' Guides

Sunday, 13 February 2011

Suzuki GS/GSX Fours


It was one of these really weird moments. There were seven of us, each armed with a different era and capacity Suzuki four, and up ahead beckoned a favourite stretch of open road... One of the smaller bikes was arguably the fastest. One of the early GS750's with a turbocharger tacked on! This was run by Eddy who if he ever spent the same time and effort put in on his bike on work would be rich and successful. Despite a big, open drainpipe of a silencer the turbo GS was strangely quiet as it came in on the power and went into wheelie mode.

My own GSX1100 was one of the last models made, was mildly tuned and lightened. Because the GS's turbo wasn't capped it could be taken to the point of self-destruction... in fact, total disintegration. If the owner wanted to risk that level of disaster he could outrun me, but there was so much time, money and effort involved in the bike that he rarely chanced the motor to that extent. So, on a good day, I was top dog! Woof, woof!

The GSX was a machine mired in both excessive power and torque but the midrange turbocharged punch of the GS had the legs on it, needing much undignified gearbox work. Luckily, the gearchange - as with most Suzuki's of this era - was still relatively slick and free of false neutrals. Even so, the GS750 owner regarded gearchanges with fear and loathing, knowing that a single false neutral would let the turbo blow the engine into a million pieces. To put the meatiness of the turbo into perspective, a decent bit of drive chain lasted only 1500 miles.

These bikes are hardcore hustlers, can keep ahead of the pack but both can loiter with intent when riding amongst our slowing moving brethren or when the cops decide to do their nuts. George owns the most immaculate bike, a totally stock GS1000, right down to its wimpy shocks, forks and triple discs. George loves to polish up the GS to a mandatory-sunglass shine but he's also good in the corners despite the bike's lack of prime suspension. Comes down to the fact that he used to do a bit of production racing in his misspent youth. Not one to be underestimated, is old Georgie.

On one occasion, by cunning use of line and position, George sent Eddy's turbo special all crossed up and on its way to oblivion, but the nutter gave her maximum stick at the crucial moment and the GS pulled out of its suicide track with a maximum slide and wild old howl. Later, Eddy tried to put his front wheel on to the GS1000's pillion perch - at 80mph! The first time I've ever seen George look seriously frightened.

Another wild card is Brian's GSX750, which runs to hot cams, ultra loud pipe (a degutted Motad, if you must know) and some flatslide Mikuni carbs off a race GSXR750, along with much modded ports and valves. Admittedly, the bike's a bit reluctant to run below seven grand and above that, in town, just about every police officer and citizen within a square mile goes berserk! On the other hand, it'll do more than 140mph on a long straight.

With much modded suspension, this is probably the best handling of the bunch, though its rider's technique leaves quite a lot be desired. Especially if you're a cager coming in the opposite direction and find a motorcycle on the racing line rather than the correct side of the road. He reckons that the loud exhaust gives all the warning that the car drivers need to keep out of the way.

Brian isn't an ace mechanic, experienced any number of blow-ups. His greatest achievement was tangling all sixteen valves! He always has a spare engine, often two, that he works on, so can be up and running in less than a day if disaster does strike.

Apart from blowing up his motor, he also likes to hit things but he hasn't managed to bend the frame yet, which must mean it's pretty tough. Bent forks and wheels are just an excuse to upgrade to better quality stuff, which is pretty easy when you consider that the stock suspension wasn't much cop to begin with and wears poorly. There's so much mass that decent suspension is mandatory.

The twin front disc brakes have their moments but caliper rot and lack of power when ridden to extremes means it's easy to end up as dead meat when the going turns dangerous. Last I heard, the GSX was running a front end off an 1200 Bandit, which judging by the angles of lean Brian could achieve suited the bike very well, indeed.

This was in direct contrast to the GS850GT shaftie, a bike that I actually had the pleasure of owning for a short time. A very short time. I found the combination of excessive mass, slow turning and shaft drive churning added up to an instant heart attack in corners. The way the other lads liked to cut each other up left no room for a slow moving slug like the GS850. Its most surprising attribute, total longevity and indestructibility, having now trucked along for 112000 miles and being currently in the tender hands of Gerry who wants to major in rat biking. Being totally broke he doesn't have much choice in the matter.

Then there are the trio of Kat's - 550, 650 and 1000 owned by Mike, Martin and Doug respectively. Who knows what fantasises ran through their minds when they opted for the still modernly styled Kat's but they don't work so well in our fast company. But then most bikes of this era don't.

The 1000 has the power but the handling can turn really dire on a whim. It was frightening enough observing the antics of the wheels from a distance - were they actually connected together? From the saddle it was a whole new deal, with bars that tried to slam-dunk their way out of my grip and an almost histrionic need to head towards oncoming cagers. They saluted the antics on their horns whilst my mind stalled dead - back off, throttle through it or loosen my grips on the bars? Sod knows, so I just grabbed all the available brakes and fought my way down to a speed that was less likely to kill me.

In contrast, the smaller Kat's are totally glued to the road, the 550 being exemplary even on worn suspension and tyres. But slow? The not so little 550 could barely chug its way up to the ton-ten, didn't really want to do more than 90mph. The 650 had a bit more blood and guts but some looseness in its shaft drive meant it always felt like it wanted to go into a self destruct act. Churn through that nonsense, it would put an honest 120mph on the clock. Tolerable, especially if your licence was about to enter never-never land... most of this motley crew hadn't registered the bikes in their names so didn't really worry about the speed cameras.

The 550 Katana, in bright red, with glowing chrome, was definitely the prettiest of the bunch. And the slowest. Even the rat GS850 will run it into the ground - literally, on occasions, when the handling on the bigger four gets out of hand!

The shaft driven bruiser can take on a rather frightening aspect, its huge mass grinding along the highway with an excess of (rotted) exhaust noise and a ringing top end (started around 79000 miles!). It weaves and wobbles all over the place, even though the suspension was upgraded about 40,000 miles ago (stronger fork springs and Koni shocks).

Figure chassis bearing life of less than 10,000 miles, once a little wear gets into the components the looseness is rapidly amplified. A GS850 running worn steering head or swinging arm bearings is not a pretty sight - rather on the same level as a charging rhino. Gerry couldn't give much of a damn, not having a lot to lose...

He has an infamous penchant for playing chicken with cagers in suburbia. The crazed blare of the engine in second gear helps things a lot, most drivers intimidated even before they have set eyes on the bike. Itself, not a pretty sight. The matt black finish matched to several layers of ex-army gear on the rider - well, his brother used to be in the army. His one remaining ambition is to mount an imitation machine gun on the petrol tank - at least he claims it's a replica, no real knowing with clowns like Gerry!

Just occasionally, Gerry gets things seriously wrong. Once, he tried it on with a Transit van which didn't budge an inch. He ended up going into the pavement on the wrong side of the road. The front wheel hit the kerb at a dangerous angle, sending the bike into a dervish dance that almost broke his legs before he sorted it out. The cracked up kerb testament to the inherent toughness of the ancient Suzuki.

Given that the brakes barely work and that the faster it goes the more determined it becomes to stick to its chosen line, Gerry rarely played chicken on the open road. The bike would probably survive but the ensuing carnage turn Gerry into a walking vegetable. Some people think that extended exposure to the GT has already got him halfway there.

Though I don't usually like to admit it, much of the inherent GT's instability has been passed on to my own GSX11. It's a pretty good bike when everything is up to scratch but let just one element get a bit too worn, the handling can degenerate rapidly. On one 200 mile saunter, it went from feeling very solid to twitching and shaking coming out of each and every corner.

I ended up grappling with the bars on several occasions, had to go easy on the power. That was a perennial problem, anyway, because its excess of horses would wheelie the front end without much effort, resulting in a total absence of any controllable steering!

I eventually pulled over, kicked the front tyre in the search of an easy answer, and when that didn't work checked out the tyre pressures, because the bike only held on to its stability within a narrow band of tyre pressure. That was okay but I thought I could detect a bit of looseness in the forks, so tightened down the steering head stem a tad.

This turned out to be a very bad move as the bearings were notched, causing some really dangerous speed wobbles at as little as 60mph. I backed off the steering head a touch, was able to make it home in one piece. Taper roller steering head bearings work extremely well but only after they have been set up to perfection with regards to steering head stem tension. Get it slightly wrong, the front end feels far too loose or heavy.

When I bought the bike it came with Ferodo pads, Goodridge hose and a pair of skimmed discs. For most of the time the front stoppers were adequate, but nothing exceptional. I soon upgraded them to GSXR calipers, which had so much more braking power I thought I was riding a whole different motorcycle. One that majored in the good old cut and thrust.

What I didn't realise at the time was that the skimmed discs were heavily distorting under all the new power, eventually cracking up. Fortunately, the desperate noises and lack of power warned me before the brake had a chance to fail at speed. Doesn't bear thinking about, 500-odd pounds of GSX11 ploughing into a cage or bus.

GSXR discs were adapted on to the GSX wheels and all was well with the world. For a while. I've never come across an old Suzuki four with discs that were anything other than finicky, some suffering from a disturbing lack of feedback, others fading when the going got tough. Combining components from various models is a bit of a cult amongst owners, GSX11 calipers being a particular bugbear as they don't provide enough leverage.

I don't know how it happened but I even managed to split the right-hand run of Goodridge hose, brake fluid spraying everywhere and the front brake doing a runner just as I wanted to pull up for a busy London junction. Catastrophic brake failure all too common amongst our pack. The GSX has scads of engine braking, also makes a lovely howl on the overrun. The back disc was never anything more than a fairly remote back-up, but we managed to skid to a halt a mere yard over the white line. The cagers didn't appreciate the near miss!

At least the engine has been amongst the toughest. The totally indestructible one's the little GS550, which could survive for a 100,000 miles, or even more, with little other than the odd oil change. Its toughness came from sharing many components with the GS750, reflected in the GS550's excessive mass. A combination that doesn't add up to a lot of blood and guts on the road, even when the full complement of 54 horses is on board. A little bit of clutch rattle at tickover is normal, should disappear when the mill's revved.

The GS750, in stock form, is thought the most useful of the whole GS range. Having much of the 550's handling stability and lots more performance, 125mph against 110mph and plenty of high speed acceleration. The 750's engine problems are mostly down to neglect of the top end, the exhaust valves being the weakest element.

Once some serious tuning's undertaken, especially stuff like the full-on madness of a turbocharger, the 750's bottom end can break up, but it does need some very serious abuse to achieve that. Clutches are prone to explosion when subjected to lots of wheelies and Eddie has even broken up the whole gearbox when he went totally mad! He has these insane moments, much to everyone else's amusement (including his bank manager).

Both the GS650 and GS850 have a bit of reputation for top end problems - valves, cam lobes and even the usually excellent automatic camchain tensioner can stick. Weak piston rings are also not unknown and it's possible to seize either engine at speed.

Somehow, Gerry's 850 mill has escaped this fate, despite both of us trying to destroy the motor at various times. Perhaps an easy early life or wisely run in or the luck of the draw with all the production tolerances running the right way. I suspect most of the 850's were neglected something rotten, suffered accordingly, whilst the 650 Kat was the kind of bike that was thrashed by ageing youths (that's us, folks!). The shaft drives tend to wear, go very loose, but don't actually fail. Overengineered, I think they call it.

The GS1000, perhaps because of its sometimes beastly handling at speed, usually survives well because few people are really able to thrash them. It's most likely to ruin its clutch and beyond 60,000 miles I've come across a couple that have had rat-like gearboxes (a useful way to check out if the mileage is genuine). Heavily tuned examples usually suffered from extensive crash damage and can blow their crankshafts.

The GSX750 and 1100 can be as long-lived as the GS's but they do need much more regular maintenance sessions, especially as regards the 16 valve heads. Neglect them, you're in trouble. Simple as that. The engines smoke heavily on the overrun when there's valve trouble, as well as making a lot of top end noise.

Don't know why, but about half the GSX750's I've come across have needed extensive work around 55-60,000 miles - new valves, rebore, camchain etc. A few have made it through the 100,000 mile barrier without any work. Again, the 1100's are so meaty that few people managed to thrash them. Certainly not if they were running to the earlier twin shock set-up which unless upgraded could turn very vile in the corners. On the straights, as well. The front end on the later mono-track varients can turn very light and flighty, causing more accidents.

As well as sometimes finicky valves and camchain tensioners, look out for dodgy clutches and the final drive bearing gone all slack. You also have to know what level of vibration's normal on the 1100, worn ones becoming a bit frenzied after 7500rpm. My own hit a patch of buzzing between 5500-6000rpm, which coincided with a hole in the power output, but this has always been there, hasn't gone any worse over time. Some bikes have it, others don't.

I've know two Kat 1000's go down from engine problems in less than 50,000 miles, they seem to run very hot, warping internal components which leads to high speed seizure or the valves trying to coalesce with the pistons. Total engine write-offs not unknown.

Early versions of big Kat's suffered from very temperamental carbs, along with other GSX motors needing relatively frequent balancing sessions. Way out of balance carbs can contribute to heavy vibration, a useful bargaining point if you're sure it's the carbs that are at fault (and the vendor doesn't know the cause). Because of the big Kat's brutal handling, redone cosmetics can hide serious frame damage, the subframe, for instance, quite likely to snap off if you try to straighten it.

A common problem with all GS/GSX fours is the exhaust system, which basically rots away merrily as soon as it's fitted! Even OE replacement systems are shorter lived than the stuff that comes on the bike which can last for half a decade. Lack of out of town riding can contribute to early demise as it fails to blow out the condensation that collects during town riding.

The GS series can take most stuff available in the breakers, any silencer of a vaguely similar length will do just fine. Try that lackadaisical attitude on the GSX series, you'll end up with holed pistons and/or very poor running. Even something decent like a Motad often needs a carb upgrade when fitted to a GSX750 or 1100, but at least there's a vague approximation to the engine's characteristics.

One four into one I tried (which had better remain nameless for legal reasons) really did for the power output. I spent a small fortune on replacement jets and freer flowing airfilters to little avail. Even the local engine guru, equipped with a dyno and decades of experience, gave up in disgust. He could either get a wacky top end or lumpy low down torque but not both together.

In the end, the four into one's 'silencer' was dumped and a stock GSX can fitted. This worked exceptionally well, all the original low end torque with a bit of extra go at the top end. As well as pushing the fuel closer to 50mpg than 40mpg. The GSX11 had always been exceptionally frugal for such a big, fast motorcycle. Don't know why, in fact it was better than most 750's.

Of this motley bunch, though, the little Kat 550 came out on top with an easy 60mpg, often better yet. The worst was the tuned GSX750, often down to less than 30mpg, running as expensively in town as on the open road.

The new exhaust allowed me to break through the 150mph barrier, which was a lot better than the tuned GSX750's 140mph (the last 10mph of which needed an excessively long road - the M1 was ideal but the plod didn't concur) and even had the turbo GS750's owner cursing. Theoretically, he could go faster but the price might well have been total engine disintegration - no fun at that kind of speed.

To be honest, none of the bikes capable of speeds in excess of 120mph could be described as being brilliant in their stability. Bad road surfaces could lead to some wild wobbles but there was no predicting which bike would be susceptible to which road surface, other than to say that the 1000 Kat usually let loose first. Made for interesting times - just as well none of us were Chinese, wasn't it?

The other well chronicled GS/GSX problem was alternator burn-out, in turn leading to all kinds of electrical nastiness. Some reckon that it's down to lack of oil changes, overheating the engine in turn, which burns out the wiring. This is unlikely, I've known many GS owners who have suffered from alternator demise who have done very regular, as in 1000 mile, oil changes. Neither have they particularly caned their machines. Other riders who have gone into full neglect and thrash mode haven't had any problems!

All kinds of theories but I reckon that it's just down to substandard components, more so in the GS than GSX but advanced age and mileage does for them all in the end. Often, just one of the alternator coils burns out first, allowing the bike to run okay without the lights but not up to keeping the battery fully charged in the night. On the GS it's a relatively old fashioned system, with the alternator coils coming in as the lights are switched on. If one coil burns out it's possible to swap the coils around so that the battery still charges with the ignition on and lights off.

The old cure used to be a rewound alternator, Superdream rectifier/regulator and lots of lovely new wiring. Worked jolly well, at least for the smaller models, the bigger stuff could overload the Superdream components.

Nowadays, secondhand Superdream bits are rare. No-one's going to bother fitting the original stuff, wiring in components meant for a car alternator is the cheapest way out, a few quid rather than hundreds. Worked fine on my bike, although the turbo GS almost went up in flames at one point. Some of the wiring fell apart and shorted out - all those G-forces!

You won't find any of the GS series with the original wiring... well, you might, but it won't run very well if at all. At this kind of age the insulation falls off and the switches short out - a good definition of trouble! The GS650 Kat, for instance, had to be towed about twenty miles when the fuses blew and even a nail threatened to melt as the wiring burnt away. Most people end up doing a wire by wire replacement and fitting switches off something vaguely modern. You won't find a stock headlamp or horn on any of these seven bikes, either, for the simple reason that they are all crap.

Any used bike you can find problems, and its says a lot for these old Suzuki's that they are still hard ridden on the road and can be kept going, for the most part, on a fairly strict budget. Do something mad, like add a turbocharger, the expenses and complications add up... the buzz of the power coming in is addictive but then so are young women... and I can't afford them, either.

In fact, with all the plumbing plus the huge turbocharger unit the GS750 probably weighs in at even more than the unlikely 550lbs of the GSX1100 - built to last, see. We occasionally let this guy with a GSXR1100 ride with us, and it's a bit embarrassing to be nowhere in sight through the faster bends, though the power difference isn't that noticeable on the motorway.

Even our crazier riders, who don't mind turning their undercarriages into grinding-angle, can't stay with the GSXR which has disarmingly modern dynamics - it's mostly down to the radical difference in the amount of mass that the machines carry, which in turn allows all kind of trick steering dynamics.

That isn't to say that an excess of fun can't be had on the older fours. Back to that wild day when the seven of us were out and about, ready for serious mayhem as the tarmac stretched out before us. Strange things happen to a group that has often ridden together, we like to toy with each other, hold something in reserve so that a surprise, or two, turns up.

This time around the GS550 Kat had sneaked to the front, using its relative cornering agility to make it to the head of the pack. As the straight gained supremacy we were all hollering on his tail, but gave him a few moments to see if he could break through the 110mph barrier. Never seen a 550 do more, nor its engine blown up in anger, but there's always a first time.

At this point the turbo's boost cut in, the GS750 taking off like a missile, almost seeming to create a vacuum in its wake, the sheer displacement of air causing eddies in the summer heat haze. I wasn't having any of that, cut down two gears and charged after Eddy. The tacho needle buried itself deep in the red, the exhaust howl threatened to blow my eardrums and I had trouble holding on to the bars, which in turn were threatening to go twitchy.

Still, Eddy's numberplate was turning smaller. What the hell had the lunatic been up to? Finally, as the speedo touched 135mph, I began to gain on him. By then we were both down on the tank, living on limited vision and excessive adrenaline. At exactly 145mph I edged alongside, gave him a sideways glance but no way I could actually move my head under all the wind pressure.

He seemed to wink at me, started to accelerate - hard! - away! I wrung the GSX's neck all the way, right into the red, churning vibes from the final drive threatening to disintegrate it and bike beginning to feel like it was coming apart in my hands. Naw, can't hold it any longer. I had the last laugh, a trail of smoke out of the GS750's exhaust, maximum turbo boost bending the valves - again. Motorcycles, I love 'em!

I.P.