Gix11

How to "Convert a Diaphragm clutch unit to a Coil Spring Clutch unit" - Submitted by Deano (Dean Molloy)

Reasoning behind this This "How to" arose from a question from an ASF member regarding his recent Suzuki Bandit engine rebore. A donor Bandit motor was sourced for his '86 Slabby and was rebored to 1260cc. With the increased power output he noticed that his standard Bandit clutch was slipping under power and wanted to know the best way to stop this, whether it be different plates or heavy duty clucth kit. The answer to his problems was to replace the weak Bandit clutch for a more robust unit - in the case the early model GSXR coil spring clutch. Here's how it is done: Bandit Diaphragm versus GSXR Coil Spring This is a pic of the bandit and gsxr clutch baskets. The bandit one on the right is smaller and completely different design.... Below is a bandit clutch plate sitting on top of a GSXR clutch plate. The bandit one has a lot less friction material on it. Note the different ways of driving the basket on the outiside of the plate. The bandit plate is alloy whereas the GSXR is steel..... How to do the conversion Just junk the complete bandit clutch system then get a GSXR1100 diaphram clutch basket (1127 through to the end of 1074 watercooled are all the same). The GSXR 750 is a alloy clutch basket which is no good as they destroy themselves at just a hint of torque and they make a great mess of the inside of you motor, think cast alloy everywhere! Get a slabby coil spring drive, hub springs and pressure plate, put the bandit alternator and oil pump drive gear on (staight swap fit). Luckily, all GSXR1100 clutch plates and steels are the same. Make up a small spacer (about 8mm) to space out the clutch nut from the drive hub. Put a 11 - 11.5mm steel ball up the guts of the clutch shaft to space out the clutch push rod. (I have pesonally put a coil spring set up on my turbo bike, it is a 2004 bandit motor and it was as easy as it sounds). The 8mm (approx) spacer that I mentioned is to space out the hub nut that holds the clutch on the shaft. The width of the splined hub on the slabby is about 10mm narrower so that spacer is needed as otherwise you will run out of thread on the gearbox shaft when you tighten it up. The oil pump and alternator drive gear on the back of the basket will come off with the use of a screwdriver either side. You will need to use the Bandit gear on your GSXR diaphragm clutch basket. The needle bearings and sleeve are interchangable between Bandit and GSXR, not sure about the slabby bearings as i just used the bandit ones as they were only 4000km old Additional (added by Booster - Greg Watters) Instead of the complete conversion the original diaphram springs can be beefed up with spacers too, about 1/2 the difference of adding another diaphram for adding a similar thickness washer inside and out. Diaphram springs test at ~100psi each preloaded to nearly flat. Found GSXR1000 valve springs are a good upgrade on coil spring conversions on my SRAD GSXR750. Standard springs read about 50 psi on a valve spring tester at 30mm installed height, 1k valve springs read 55 psi but if you add a 1mm spacer the standard springs stay fairly much the same and the valve springs gain nearly 10 psi, with about 3mm available till coil binding would be a problem on releasing the clutch. Good luck!