As far as I'm aware you can only go to 2.00mm. DeeTee was mentioning to me that Yamaha only ever made OS pistons 0.25 .50 and .75 i think it was. Then it starts touching the powervalve. The after market ones go up to 2.00 i think but cause problems with PV. Whats your bore size at the mo?
i think someone used them not long ago, and they didnt hone the barrel so he had to get it done elsewhere, i think NORFE has used this seller before too
yeah hes done my last 4 altho iv had to chamfer the ports as hes not done it any time, and run my honing stones thru it, if ur not capable of doing this ur self send it to pjme i use him cos he does it me same day and hes local so dont bother me
each to there own on piston preference, they have to pass a certain std for uk sale but not the longest lasting items, id buy a tzr mitaka then send it to hiom for boaring, he will be able to get mitakas id of thort... yeah just chamfer all the port edges with a small carbide burr 45 degrtee or as near as poss
