FXR rear brake

[Tony G]

Hi all, has any one had a problem with the rear brake on a 1991 fxr ? i had a real problem bleeding it up 2 months back but got it sorted eventually ! today i was putting some new pads in ( so had to push the piston back ) and now the pedal won't pump up ? tried to bleed it but it won't have it. im a bike mechanic by trade so i know what im doing !!!!! i have had the master cylinder and the caliper striped and every thing is ok. the whole system looks in good order for its age so i think a new master cyl is in order ????

sorry i men't to put this in the evo big twins section !!!!!

[Kiwi]

had an fxr rear brake on one of my bikes - basically these either work or more often don't, they tend to stick and bind on

replaced it with this - a far better set up

[Tony G]

have you got a free one goin spare ????? Kiwi

[Limey_Dave]

I take it the pads have moved up to the disc and you're getting a shot of fluid out the niple each time.
Might be worth a shot with a Mityvac if you have one.

[Tony G]

Originally Posted by Limey_Dave

I take it the pads have moved up to the disc and you're getting a shot of fluid out the niple each time.
Might be worth a shot with a Mityvac if you have one.

yeah the pads are up to the disc, not getting much out of the nipple even with vacuum !!! thats why i think its the master cyl, the thing is it looks inside ?

[Limey_Dave]

This is not specific to your model but to hydraulics in general.
If it's not pumping fluid and the pedal is hardish then there's a restriction at the niple or somewhere.
If the pedal is slack then I'd say it's pushing past the main seal or the piston is not returning to the recovery position,this could be the piston it's self or the pedal/linkage not allowing it.
How did you sort the prob last time?

[Tony G]

Originally Posted by Limey_Dave

This is not specific to your model but to hydraulics in general.
If it's not pumping fluid and the pedal is hardish then there's a restriction at the niple or somewhere.
If the pedal is slack then I'd say it's pushing past the main seal or the piston is not returning to the recovery position,this could be the piston it's self or the pedal/linkage not allowing it.
How did you sort the prob last time?

the pedal is slack all the time just wont pump the fluid to the caliper, last time i did it with vacuum but today it just wouldn't have it ? ive herd that the master cyl on the fxr is crap anyway ! is this true ?

[Limey_Dave]

I can't give an opinion on the FXR,I plain don't know.I went from flathead to Roadking and it seems my '99 brakes are crap or so legend has is.
Saying that,the combination of a humpback,a tight turn,a wire fence,and fear can lock the front wheel.

[kiwidave]

search the archives. try reverse bleeding. Start with a three quid oil can and a piece of clear hose. ALWAYS works. Nothing wrong with FXR master cylinders, as a rule.

[dodgyloner]

Not had any problems with mine and its 91 also.

As Limey Dave says, I suspect the master cylinder piston may not be returning back far enough to "recharge" itself with new fluid due to pedal/linkage travel. Check adjustments are as per your manual.

If you find it is the seals etc there are rebuild kits available.