Wednesday 15 June 2011

Suzuki GSX750F

You would think I was a mass murderer or something, the amount of abuse and derision I have to put up with. Yes, I know the GSX750F ain't the prettiest of bikes on the road and from certain angles is downright ugly but it's not that bad. Spotty Herberts on bloody mopeds and hard cases on race replicas all like to take the piss. If I had a quid for every time someone has come up to me and said, "What did you buy one of those for, mate," I'd be very rich. It's the way they say it that really gets me, like I was some mental retard.

To put the record straight, the GSX750F is a powerful, light and reasonable handling motorcycle. It uses a detuned version of the air and oil cooled GSXR750 engine, having lots more low down grunt but also coming on cam around seven grand like it means business. Ultimate power is down slightly from the GSXR, but with over a 100 horses at 10,500rpm there's no lack of high speed performance. Weighing only 430lbs means it's one of the lightest 750s around. Using a steel trellis wrap around style frame, the chassis is rigid, only let down by suspension that was surprisingly soft, the bike being six months and 5000 miles old when I acquired it.

Starting was a bit hit and miss. Sometimes the engine would purr into life, settling down to an even beat from the 4-2 exhaust, which was already showing signs of rust. Other times the engine would churn over, backfire and take ages to warm up. This strange phenomenon disappeared by the time I had put 8000 miles on the clock, it may have been down to some crud in the carbs that use had cleared out or a loose connection that had become firm. Who knows?

The clutch was light, the gearbox slick; the bike could be trickled off slowly in second or the clutch dropped with the tacho at the 12k redline in first. The latter resulted in a violent wheelie but the inherent stability of the chassis meant it was easy to control. On buying the machine I took great delight in terrorising the local pedestrians until I realised that it was wrecking the chain in short order. It wasn't the kind of bike that put its front wheel in the air when accelerating in the gears as too much weight was put on the front end for this kind of delinquent hooliganism.

The bike preferred more than 4000rpm up but would run smoothly below these revs and could hold 30mph in top gear, albeit with minimal acceleration. At the other end of the scale, about 145mph on the clock is possible when tucked down behind the plastic. Anywhere between 90 and 125mph can be held on motorways blasts until the petrol runs out. For fierce acceleration during acceleration I found fourth an excellent gear as long as you were doing more than 70mph, it often being necessary to drop down out of higher gears to find that extra bit of accelerative edge.

Power delivery was not instantaneous, there was a slight lag between whacking open the throttle, even in the lower gears, and actual acceleration. It lacked the distinct and sometimes frightening edge of the GSXR but I rather enjoyed its more friendly nature.

Two things spoilt the bike as a high speed tourer. An excessive amount of secondary vibes came through both the bars and footrests - someone at Suzuki had evidently forgotten that you are supposed to carefully match the frame dynamics to the engine type. This was most annoying, naturally, between 70 and 85mph or after 120mph when it became really fierce. I could tolerate it for about 100 miles, thereafter my fingers started going dead on me. I alleviated this to a great extent by fitting some thick rubber bar grips.

The second problem was the suspension. Even with the rear shock's damping and pre-load turned up high, it was still too soft and lacked control. A series of closely spaced bumps would upset it. The front forks were basic units that were again on the soft side. The funny thing was that although the rider would take quite a battering the bike itself was stable and even powering out of curves whilst hitting bumps did not turn it into a lurching beast. I never fell off the bike and was quite happy to try to get my knee down in most circumstances; it was not the kind of bike where you sat there in fear of a sudden, frightening speed wobble.

Unlike some other modern Suzukis, steering is not upset by backing off the throttle or braking in bends. Only in the wet did it feel less than secure, the fat Metz on the back was prone to sliding out a few inches. It was but a moment's work to back off the power a touch to allow the wheel to come back into line. White lines in the wet would have the machine shimmering like some ancient fifty.

Protection afforded by the plastic in downpours was better than many other race reptiles, although hands would still take a drenching and the screen was only useful if you tried to kiss the clocks. Strangely, despite running on 17" wheels and weighing only 430lbs, the bike was heavy going throwing through tight curves or S bends. I could tolerate that as it didn't wobble or twitch very much in other circumstances.

The twin front disc brakes were immensely powerful, braking could be left to the last moment and even under the heaviest of braking the bike would pull up in a dead straight line. Wet weather lag was not noticeable although after 9000 miles there was a lack of feedback that could result in a locked up wheel. I tried changing the fluid to no avail, I guess the rubber hosing was going off and I should have fitted some Goodridge but I could not afford the expense.

The longest ride I did in a day was 350 miles. The bike ticked over like it had just gone down to the shops, but I was very saddle sore, my brain buzzing with the exhaust wail (by that time most of the baffles had rusted out) and my body shaking from the vibes. I had done short stretches over the ton but the excess of cars had kept speed down to a mere 60mph or so. The overall riding position was good, sitting low in the machine you quickly became part of the bike and it took mere minutes to feel right at home.

The bike had averaged 43mpg on that trip which was more than I normally got. Overall average is less than 40mpg, sustained high speed work, keeping the speedo over the ton all the time returns about 35mpg and gentle riding never betters 50mpg. It doesn't consume oil between 3000 mile changes, so that does save some money. If it's expensive on fuel, that's also true for consumables. Metz tyres last for no more than 6000 miles and even the O-ring chain doesn't better 8500 miles, whilst pads were down to the metal after 6500 miles on the front although the rears have not been touched, mainly as I hardly use the back brake.

Expense doesn't stop there as the engine requires a full service every 3000 miles at around £100 a time. The plastic is easy to remove, the valves have screw and locknut adjusters and little else needs adjusting apart from balancing the carbs, so I guess my local dealer is the usual rip off artist. Unlike older Suzukis, the GSX does go off tune if it doesn't get its regular service, performance below 5000rpm goes very flat.

Replacing the O-ring chain myself I found that one of the rear monoshock's bushes was already worn (at 8500 miles) - you have to take the swinging arm off just to change the chain! I replaced that and greased all the bearing surfaces I could find as there are no grease nipples.

I've now done 12,750 miles. The engine is running as well as ever, the plastic buffs up as new and I have become used to the machine's limits, being able to swing it round like a much smaller bike. However, the exhaust is rotted through, rust is creeping out from under the frame paint and it's started to blow light bulbs all the time, as if the dreaded Suzuki electrical demise is about to pounce.

Perhaps the best thing about the Suzuki is its price. I bought my 1990 example for £2500 which compensates for the high running costs and gives one hell of a lot of horsepower for your dosh. I've even grown to love its looks, at least it's a bit different. A new shock and exhaust should set it up well for the next couple of years.

Adam Clarke