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My rear caliper is beginning to lock up again. I wasted 45 bucks a month ago and got the OEM m/c rebuild kit from a dealer but apparently that is all nought.

What has happened is that the rubber seal around the m/c spring has flared up thus causing too much fricition and refusing to return after the pedal is released. Im planning on subbing the entire cylinder assembly with another one. Of course assemblies are hard to come by, so I was wondering is all japanese bikes use the same banjo bolt/hose attachment sizes?? I know almost all yammies from the era will also match mount holes for the rear m/c I was just wondering if honda and kawi m/c's would fit the yammie brake hoses.

Thanks

cut the rubber boot off of it and see if it works.if it does keep riding.i have bought old bikes that didnt even have a boot on them and they worked ok.

This rubber seal is inernal or external? If it's inside the m/c and in contact with the fluid, it may be designed for use with a different spec brakefluid than your useing.

If it is the seal I am thinking of, on the actual calliper, then it's primary reason for being there is to stop road grime getting onto the slide which will eventually cause pitting. Try a bit of copper grease or molyslip on the slide, this should reduce the friction.

Not having it is not a major trainsmash, but if you can sort it while it is in situ, all the better. Another idea is if you can trip the lip of it slightly, this can reduce the amount of friction it causes, but go with the copper grease first.

All the best
S

No problems on the caliper end.

http://www.h-e-l.co.uk/HEL_Performance_ ... linder.htm

The seal described in the link above is the problem. When I removed it is was flared up like a cone. When I bought it it was a proper cylindrical shape.
Note: this is not the seal that prevents fluid from flowing out the master cylinder (that is supposed to be flared).

As a result of the flaring, the fluid return as shown in the second diagram may not be taking place correctly. Still I've also read reports that the m/c on this model especially has a tendency to lock up, which is why the rear drum brake models were preferred later on. So Im hoping a different m/c altogether mght help. Technically the master cylinder and caliper should be independent on each other so long as the cylinder bores are comparable and of course hose fits.

Manual says to use DOT3, thts what Im using <shrug>

Totally blows man!!

www.yoyodyneti.com has a brand new complete brembo master cylinder assembly that i can get for 50 bucks incl. shipping. which is 5 more bloody bucks than what i spent on that craptastic rebuild kit. Man OEM is a ripoff I tell ya. From now on, Im looking to replace everything I can with aftermarket stuff when it dies on me.