'85 250R rear brake issue
Issue: I've only got about 50% of braking power at the rear. It will lock up on gravel but not on pavement.
Back story: This is a machine that I only ride once or twice a year. A couple years ago, it started loosing brake fluid in between yearly rides. I've never figured out where it goes. There are no visible leaks but the reservoir will just be bone dry. The point is that the system has been empty in the recent past. This year it wasn't empty but I topped it off and bled it. I've now bled it several times and even reverse filled it from the bleed screw but I still can't get full power. The pedal is firm. I checked the caliper for function and the pistons extend just fine. That just leaves the master. It's never had anything done to it, never been off. I've been religious with flushes so it hasn't been neglected.
Question: Can a bad master cause this symptom?
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'85 ATC250R
.030 Over Wiseco
FMF Pipe/Answer silencer
36PJ Keihin
K&N
Boyesen reeds
Magura hydraulic clutch
Roost Boost
MSR bars
OMF swingarm skid
ITP Beadlocks
Three Wheelin' Since '84