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On my 750 Sport I've noticed that after a long ride (long = more than a hundred or so miles) the bike gets harder and harder to shift. I have also noticed what looks like clutch fluid accumulating on the bottom of the clutch cover.

I pulled the cover last week before the MotoGP race and noticed something odd. I was expecting to see fluid seeping from the piston on the inside of the cover. It was bone dry, and showed no signs of fluid ever being on it. So I started looking at the banjo bolt and bleeder nipple. The area around these two items was, on closer inspection, apparently the source of my fluid on the bottom of the cover. The bleeder nipple, when loosened, seems to have a lot of movement side to side in the threads. The clutch hose & banjo bolt look to be in good condition.

So now what? Does that mean my clutch slave isn't somehow damaged or worn out? Can a leaky bleeder nipple cause similar behavior?

try this ,it may help. 1)pull out the bleeder nipple, clean it and wrap teflon tape around the threads. careful not to get it on the mating surface of the tip. 2)flush the system with fresh brake fluid or ,if needed, pull out slave cyl and clean, you may need a new o-ring,3)on the master cyl cover there are two bleed passages near the screw holes that may be blocked. if blocked, this will cause a slight vaccum in the master cyl which in turn will limit slave cyl movement. this condition can also be caused when the diaphram under the cyl cover becomes so squashed that the rubber is squeezed into the passages blocking them. a quick fix for that condition is to loosen the cover and lift it just a little and pump the cyl a few times. let me know if this works. blaster ps, if the problem is mechanical i have some ideas for that.

Don,

The bleeder seals by the compression of the cone into the seat. The looseness of the thread isn't the issue unless it's nearly stripped and can't hold the load to keep the cone sealed. Pull the bleeder screw out and inspect the threads on the screw but more importantly the cover. The cover is aluminum and it will be much easier to strip the cover than the screw. Clean the cone and inspect the seat in the cover for pitting or wear. If they are good, put it back together and bleed the crap out of it. This design is very hard to fully purge the air from so I use a BIG vacuum bleeder to perform this task.

If fluid can get out, air can get in. If there is air and/or moisture in the clutch hydraulics it will not function propery. The reason that it's worse after riding, is the heat generated by the engine boils the water in the system and makes it expand and become a gas. This adds "air" to the system and causes the system to work at less than 100%. Once the engine cools and the gases shrink down or go back to water the system works better.

It's best to flush the clutch system once a year. I do this every spring before the riding season.

Good luck,

You guys rock! I'm going to try these tips before tearing it apart for a seal replacement that it might not need. Thanks a bunch, I'll let you know Saturday how it all works when I get it back together.