My '94 R100R with 15K miles suddenly after decelerating from highway speed went into neutral and wouldn't engage any gear. The clutch pull became abnormally light. The clutch cable and external linkage all appear intact. After rotating the the rear wheel back and forth with the bike on the centerstand, shifting gears and jogging the engine with the starter motor, the transmission and engine became engaged again. I made it home (~20 miles) but the trans went into all neutrals 2 more times, both times after a deceleration to a stop. I was able to engage it both times after jogging the engine and rotating the rear wheel. I am the 3rd owner and am unaware of the circlip status. Any suggestions as to the root cause would be appreciated.