[headshrink]

Originally Posted by setasai

Seeing as you've isolated it to the engine, seems like i'd go with either the gearbox or clutch assembly. Since the engine is still new and seems to pull just fine, I say change the oil a few times and see if it goes away. Does it occur in neutral? If not then maybe it's the gearbox.

I don't know if it occurs with the gearbox in neutral... I'll test that out on my way home. Might be a little challenging to get it cleanly into neutral, but I should be able to do it.