If you've had this problem and determined that it is not a faulty starter "O" ring, this might be of help.
I was mystified by this intermittent oil leak from a drain hole on the shifter side of the lower crankcase. It was worse when it was cold outdoors. The forward shaft drive oil reservoir would also fill with motor oil. Dirty oil would pour out when I removed the oil level check screw
In the end, as noted in the original post, I decided to re-torque the crankcases. It took me a while to get around to it. When I did, I discovered that all of the fasteners were properly torqued with two exceptions: the two bolts that run on either side of the oil filler cap for the shaft drive.
The bolts run all the way through the crankcase and have nuts which are accessible on the bottom of the crankcase, in front of the shifter shaft. I took the side cover off which made seeing/accessing them easier.
After tightening the two bolts & nuts at both ends, I have run the bike for two weeks without a drop of oil seeming to leak. The shaft drive oil has stayed at the proper level and there doesn't seem to be any engine oil migrating where it shouldn't.:-D
The previous owner had the shaft oil changed. I wonder if whoever did that loosened the two bolts on either side of the filler cap by mistake.
CCMcC
'82 GS850GZ
'88 Husqvarna 510TE
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