Bought a DT2 from a fellow about 5-6 years ago. He had a stable of bikes and a good looking fully restored RT2. Had a pan up under it and said it had a small oil leak. Fast forward two weeks ago and I bought a slick Rt2. Feller said it might leak a drop or two of oil. Well sure enough it does. I haven’t looked at it yet, but, is there a likely culprit?   Something that is more than pretty common? With these bikes? I just thought it strange that these 2 rebuilt bikes had oil leaks on the same side, gear shifter side. I know nothing about the rebuild or what they did to them. Here’s a picture of the one I bought. Thanks in advance!

There’s quite a bit of aluminum castings that move a bit when warm… so in all reality, we should expect a few drips… learn to keep an eye on the fluids… we all need to replace some gaskets/seals… the nature of owning and having fun riding these old relics…
Sneezles61

Only realy 3 options for trans oil on the left. Change shaft. Sprocket shaft. Pushrod seal. There is a blanking plug there too over the selector drum case hole but never seen one leak. Also on the side stand the trans drain bolt & selector drum cam pin bolt are both possibilities but unlikely. Best bet is clean it off & sleep with it with one eye open. Oil can run & mislead us sometimes.

Oil leak on the left side you say? On my DT2 I had an oil leak. Ended up being several oil leaks before it stopped. Clutch push rod seal, primary shaft seal, shifter shaft seal, left side crank seal, kicker shaft seal, O-ring on the tach drive assembly, right side case gasket, autolube pump drive shaft seal, autolube pump gasket to case, cylinder base gasket. With the bike on the side stand the leaking oil would travel to the left side making it hard to narrow down where the leak was coming from. The 2 stroke oil would turn from the Yamalube bluish/green to a yellowish/brown once heated up in the crankcase making it hard to determine if it was 2 stroke or transmission oil.