Found rebuild kits for '82 XJ1100J front calipers. Tom @ Yamaha USA Customer Relations says the part # is 4LO-W00-47-01-00 ($38.16 for the 2 seals, enough for one caliper). Or, if you also need the piston, part # 4W1-W0057-00-00 = 2 seals + piston, for $65.80. Have not confirmed proper fit for following, but there's also a chance that Old Bike Barn part #29-0126 would also fit the XJ (it has the 2 seals and rubber cap for bleeder fitting for $23.95). Says it will fit the '82 XV920J. I believe that uses the 38x41.3 mm piston, so that kit should also work for the XJ (I'm probably going to get the OBB kit and test the theory.
Pegasus54
Pegasus54