Yamaha Big Bear 350 1992 slipping clutch

[Ulf Löfstedt]

I just bought a Yamaha Big Bear 350 from 1992. The previous owner has run it on regular engine oil and I have problems with the clutch slipping. I think that's the reason.

So what should I do?

- Just change oil and it will be OK?
- Clean engine/clutch + new oil?
- Or do I need a new clutch?

It is guessing the centrifugal clutch that slips. It has two clutches , it also has a "regular" clutch .

Anyone who has any experience of using wrong type of oil?

[Tim-ANC]

Change the oil. There should be an adjustment screw that squeezes the clutch plates together. This reduces excessive gap between the plates caused by normal wear.

I don't know where it is on your machine. Hopefully some one else will respond with that.

[Frank Angerano]

I would drain the oil, pull the cover and inspect everything. Maybe an adjustment or new plates and springs might be in order. Who knows what the previous did. He may have beat it up a bit.  But I would definitely take a look inside.