It's ThuperTune time again, folks, and this month it's Suzuki's GSX-R1100. This is the bike that started and wrecked more tuning careers than anything else in the history of the universe. Remember, all prices quoted here are inclusive VAT. The GSX-R1100 has only had three major engine overhauls compared to the GSX-R750's five. Phee-ew! There's still a whole shedload of stuff to get through and only five pages to do it in, so V&M and Performoto were the tuners assigned to the task. Remember, the GSX-R1100 has been raced and dragged more times than anyone's had hot dinners. 300bhp and 1400cc are possible, but on SuperTune we're going to stick with stuff that works for the road at the smallest possible price. Well, nitrous doensn't cost that much... Company: V&M Racing Contact:
Mark Hindle 1986-1989: GSX-R1100 G,H,J models 1052cc, 34 mm carbs "On any of the old 1100R motors the valves will be more likely than not worn. First thing to do is get a compression check, then a valve job and cylinder head clean-up if you want decent power gains. Fit a Stage 3 Dynojet kit and individual K&N filters for the induction. The 34mm carbs are okay, but there wasn't airbox technology then that there is now. Cobra still do the best full exhaust system for the R, though any good 4-1 is alright." "If you want it to go like a rocket, fit 36mm Mikuni flatslides - lovely. After that you're looking at an 1109cc Wiseco big-bore kit. We'll do a ride in, ride out service for customers, and if you want the carbs to go with that size you want 38mm flatslides. Even lovelier. Good 15% power increase right across the rev-range with that lot, easy. We also offer a full range of camshafts for the early GSX-Rs, from full race to street tune. Horsepower=pound notes with the 1100s. For the road, we'd re-profile the standard cams. For the serious boys there's a 1216cc big-bore kit available, but that's as big as it goes and there's no room for error." "Compression? Don't go above 12:1 or you're asking for trouble with today's fuel. A 5º ignition advancer crispens up the low and midrange, and Dyna coils and Taylor ignition leads replace the standard crummy items and ensure a big, fat spark reaches the plugs. We'd then fit a kevlar clutch with stronger springs to take the extra power, which jumps from the standard 105bhp to 115bhp with decent Stage 1 work." G, H, J model mods
1989-1991: GSX-R1100 K,L,M models 1127cc, 36mm carbs, 40mm carbs (M) "Most powerful engine of the lot. Engine makes 120bhp standard, heaps of torque. With race exhaust and good jetting, we get 146bhp at the back wheel out of these. 36mm Mikunis are a good set of carbs, but make sure they're derestricted before you start any work. Stage 1 and Stage 3 induction kits both work well, and you don't lose any midrange with a Stage 3 kit. You're looking at a 5% power gain with a Stage 3 kit over de Stage 1 kit, but it costs a bit more and takes more setting-up. Exhaust have got to be Vance & Hines, Yoshimura or Skorpion. We try and steer people away from putting open cans on the standard twin muffler system - it causes headaches. "Big-bore kits start at 1186 on these engines and go as big as 1260, but that's real big - no room for error. Thirty-six mil carbs can cope with the bigger bore no worries, and we 'd recommend a Stage 1 headjob to go with the big-bore conversion. The heads respons well on these motors - I've seen 7bhp just from a headflow itself. Bigger valves are available, but the standard sizes are enough for the road." "GSX-R boys are real fanatics, and we can take the 1127 motor as far as they want. Stage 3 headflow, bigger valves, race valve springs, radical cams, flatslide carbs - it's all just a question of money. We do drop-in cams for the K and L, but moving on to the M-model with 40mm carbs and they're nothing but problems with Stage 3 induction kits. Stick to Stage 1 - the airbox is fine - since the carbs are too big for the engine and you'll lose heaps of midrange with little top-end gain if you fit Stage 3. Just de-restricting the carbs properly gains you 9bhp. If you want to make an M-model fly, fit the 41mm Keihin flatslides. You've got to learn how to use them properly and they cost, but boy do they work. NOS nitrous kits are available - we prefer to fit them ourselves - and don't fart about with K or L forks. Just send them straight to Ron Williams at Maxton. A 5º igntion advancer crispens the low-end power, or try a Vance & Hines Powerpack, which lets you change the ignition curve to suit the tune of your GSX-R. Yoshimura and Skorpion are the pipes to go for the M." K, L, M model mods
1992-1995: GSX-R1100 WN,WP,WR models 1074cc, 40mm carbs "It seems pretty strong, but we've not worked on as many as the oil-cooled engine. There's no stage 3 Dynojet kit available for this bike, so life's much easier and the airbox is very good, anyway. If you want to go past Stage 1, you'll have to fit 41mm Keihins straight away. so tough. Skorpion, Vance & hines and Cobra exhuast systems all work well on these models, and the Wiseco big-bore kit takes it out to 1117cc and 12:1 compression. Nice power, but we just fitted a WP with the pistons from an 1127 GSX-R. Worked very well - we estimate 160bhp." "The standard heads are very good on the watercooled engines, and you can fit the 38mm carbs from a GSX-R750L. Not as small as the 36mm carb, not too big like the 40mm carb, the work well. A 5º ignition advancer again helps in the low to midrange, pulls you that little bit harder out of the corners. Other than that, the usual GSX-R stuff about money=power applies." Watercooled GSX-R mods
Company: Performoto Contact:
Jon Bickerdike 1986-1989: GSX-R1100 G,H,J models 1052cc, 34 mm carbs "With the old GSX-Rs, we've consistently had good results with Yoshimura exhausts. They're always good for GSX-Rs, from steel to titanium systems. We also do an aluminium respraying service which stops all steel exhausts corroding. Use a Stage 3 Dynojet kit and Ramair filters - they're just easier to use on these bikes because they're foam and flexible. The 38mm carbs from the GSX-R750L are brilliant. Go straight on using 750 manifolds, and take very little setting-up. But be careful of bodged carbs. Run a 5º ignition advancer, but only on stock-ish engines. You'll run hot on highly tuned motors." "We do two big-bore kits. The 1109, which is easy, and an 1196cc kit, which is a lot more work. Goes bloody well, but the customer needs to bring us the block from a K or L engine for that one. You'll see 130bhp easy with that conversion, though. Heads will definitely benefit from a gas-flow and the valve seats need re-cutting, but they've got to be set-up right. Cam wear can be a problem on old 1100 motors, so we send ours to Kent to be re-ground and with a more powerful profile. Oil? We use Rock Oil Fully Synthetic." "We also do fitting kits to convert Slingshot wheels on the older GSX-Rs, as well as Nissin brake conversions for decent stopping and our own fork rebuild. We use more oil in the forks and change the spring rate with spacers. Use an EMC or Öhlins rear shock in the back, and off you go." G, H, J model mods
1989-1991: GSX-R1100 K,L,M models 1127cc, 36mm carbs, 40mm carbs (M) "40mm carbs are a bit big for M-motors, so if you're leaving it stock fit the 38mm 750L carbs. They're blinding carbs, we fit them to everything. K motor is best GSX-R motor, ports are good size, it's strong and very powerful. 140bhp is not beyond the bounds of belief just with a pipe and jetkit. 150bhp is easy and you can keep it rideable, too. Fit a Stage 1 kit for an easy life. Stage 3 works about 5% better but takes more setting-up. Use a Yoshimura exhaust with a 'quiet' rave baffle, or use a Cyclone system if you're going racing. Again, a 5º ignition advancer frees-up the bottom end, and the 750L 38mm carbs go straight on. Dialling in the stock cams is worth 5bhp alone." "An 1186cc big-bore kit goes straight in, but the 1216 option isn't recommended for the street. The 40mm carbs of the M respond well to the bigger bore conversions, but it's worth going to Stage 3 on the induction if you're hogging it out. One thing I've noticed about all the 36mm-40mm GSX-R carbs is that they're very sensitive to float height - make sure it's right." "There's nothing wrong with the K-model frame, it's all the suspension's fault. Maxton do a top job on the forks, and we do a ride-height adjuster for the rear. Our rear sets are trick and save 1.5 kg off the weight, and use a Sprint steering damper because the standard ones are rubbish. Ferodo Supersport pads are the business, but the master cylinder is naff on the K and earlier GSX-Rs. Use an RC30 number. We fit the K swingarm onto the M, which quickens the steering no end, and a dead sexy Brembo rear brake set-up which saves another 1.5kg of un-sprung weight. Crashed yer bike? No problem, we do a beam-frame conversion using H30 alloy. 7/11 conversions are a straightforward, and our engine covers are unbreakable, unlike the stock items." K, L, M model mods
1992-1995: GSX-R1100 WN,WP,WR models 1074cc, 40mm carbs "They designed the motor round a bigger bore and higher compression, and then de-tuned it. Very odd. These water-cooled engines love compression, and 13:1 works well on the street. These motors don't necessarily need a Dynojet kit - we play around with the mains and move the needle on this model. Fit a K&N filter but leave the rest of the intake alone. Replacement exhausts are a bit of a bugger on the watercoolers - Termignoni is the only one I've seen fitting properly" "Skim the head for more mid-range, and fit a 1192cc kit if you want serious dollops more torque. The standard cams need to be re-timed, but a Yoshimura inlet cam, used with the standard exhaust cam, works very well. You could try the cams from one of the water-cooled GSX-R750s. They go straight in, help it rev all the way. Leave the ignition alone on these bikes, and fit a Kayaba rear shock for better ride quality." Watercooled GSX-R mods
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