Replacing Clutch Slave Cylinder Seals on an FJ1200/XJR1200/1300


Although this article is based on my experiences with an FJ1200 motor, the XJR1200/1300 are more or less identical, in fact most bikes with a hydraulic clutch setup will be similar.

So how do you know that the seals on your clutch slave cylinder are (to put it technically) knackered?

Well usually you don't until you've either got no clutch or changing gear (particularly down) becomes difficult.

The other dead giveaway on FJ/XJR's is when you go to change your oil filter, (which lives just below the clutch slave cylinder) and the paint is coming off the top, of course if you don't know the bike's history it may be from a previously fixed leak, so look for fresh bubbly/flaky milk chocolate, no I mean paint (bloody advertisin').

Do Not remove or disconnect any hydraulic hoses or pipes, you don't need to, and the job's a whole lot harder if you do.

So where exactly is this clutch
slave cylinder thing, it's shown above, highlighted.
Oil Filter Carrier, complete with missing paint Nip along to your local dealer or mail
order folk and get a clutch slave cylinder
seal kit, costs about 10 earth pounds
Undo the three bolts which hold the
cylinder onto the engine.
10mm socket or in my case a
5mm allen key.
Having removed the cylinder observe the cruddy mess within
Remove the outser dust seal, it should just pull off
Gently squeeze the clutch lever a few times to puch the piston out.
At his point you'll either forget/won't know that there's a spring behind the piston and the bugger'll pop out splashing brake fluid everywhere, clean it of all paintwork with soapy water. Remove the cap of the clutch master cylinder, cover any paintwork with cloth. Sook out the old brake fluid with a syringe (get one from a friendly nurse) and clean out the inside of the cylinder with a clean lint free cloth (i.e. not a bit of a fluffy jumper)
This bit really depends on how long it is since the the fluid's been changed, in this case it's been a while. Pour some new brake fluid into the master cylinder and poke about with a lolly stick or something similar You may find that a load of bits of gungy poo atart floating about in the fluid, poke about until it's all floating about, remove the fluid and gungy poo with the aforesaid syringe. Then clean the inside with a lint free cloth blah blah. It should be all nice and clean now.
Use a bit of old 1200 wet & dry and gently clean the bore of the slave cylinder, gently I said, you want to polish it not put great divot sized scores in it.
Remove the old seals from the piston with a small flat screwdriver, try not to stab yerself in the hand with it.
Give the top of the piston a clean with a bress brush if it's a bit grotty.
The smaller seal is the piston seal (left) the other is the dust seal (right, duh?).
The piston seal goeas on first, gently! stretch it over the piston, hollow/concave/ cupped whatever, bit goes to the back, i.e. towards the spring. Get this wrong and the first time you pull the clutch the fluid will casually wander past the seal and cause chaos throughout the universe, you've been warned.
Smear a little clean fluid around the inside if the slave cylinder and gently push the piston in, being careful not to damage the seal.
Fit the dust seal around the piston and flip it up (pic 2). Press the piston home with your thumb, or other suitable appendage, then turn down the dust seal making sure it slips into the groove in the slave cylinder. If you've done this correctly then when you take your thumb off the piston should stay in.
Before refitting the slave cylinder pull the push rod out and give it a clean.
Bolt the slave cylinder back onto the engine (Don't overtighten the bolts), put an 8mm ring spanner onto the bleed nipple and attach a suitable bit of clear hose.
Sook some new brake fluid into a clean! syringe (or wash and dry thoroughly the one you used earlier) hold it upside down and squeeze any air our (like they do on ER), attach it to the tube on the slave cylinder (sorry forgot a photie of that) open the blead nipple a half turn or so and force the fluid into the tube until it appears in the master cylinder.
Once some fluid is in the master cylinder close the bleed nipple and top up the master cylinder. (With new fluid of course). Test the clutch by pulling the lever, it should be firm, if it flaps too easliy back into the bars then you may have to bleed the sysem again in the normal manner. The syringe way usually works for me. Screw the cap back on and Bob's yer Auntie's Husband.
Road test the bike, if the clutch is ok ye can go off to the pub.

Disclaimer, of course, attempt this and any other tips on this site at your own risk, make a ragin' arse of it and it's yer own fault ;-)
Good Luck