OK, it's been too long since I had a vintage bike out of the shed. What does everybody use in TY175 and TY250? Is it ATF?

Hi, Garry. I use Yamaha motorcycle 4-stroke transmission oil in my TY250A. It's the lighter grade offered. I think it's 10W40. Charlie told me once that he used ATF in his TY250.

Thanks for the reply, Tom. Jeff called and said he had used the ATF also.

Upon further review, I have been using 10W30 Yamaha 4-stroke engine oil in the TY250 gearbox. It makes the clutch work well.