However, you might check the 'steps' of over-sizes as the OEM Yamaha pistons used to be in increments of 0.25 mm whereas pattern pistons might only go in 0.5 mm variations. There are NOS items on eBay.
This one looks OEM @ Ø64.25 mm:
272510496938
I hope that information helps
Re: Yam piston
Posted: Wed Jan 11, 2017 4:52 pm
by betty2015
Thank you
Re: Yam piston
Posted: Fri Jan 13, 2017 1:37 am
by bazza3004
Ive used 'yambits' a few times for pistons and always found them good to deal with.
Re: Yam piston
Posted: Sat Jan 21, 2017 1:36 am
by Fast n Furious
If its the Banshee piston, you may have problems with the 2nd ring peg position. With some cylinders it will drop over the inlet port.