Yamaha 760 Piston measurement Wiseco 85mm 757M08500?

[MTRHEAD]

Can someone please measure a brand new 757M08500 Wiseco for a Yamaha or Woosner

Note please measure the fattest part “about 1/2” up” from bottom usually is fattest on latest Wisecos I’ve seen

The ProX 85mm 01.2514.100 is 84.91mm or 3.343”.

Is the Wiseco 85mm (3.3465”)? Or is it 84.91mm too? Even smaller?

Thank you

 

[WFO Speedracer]

The pistons are always undersized to account for the clearance 84.91 piston for 85mm bore leaving .009 or .0035 " piston to wall clearance which is way too tight on a Wiseco piston. On an 84mm bore bare minimum would be .0005 and it really needs to be .0006 or .00065 "

Even a cast piston like OEM. WSM or PROX would need .0004 -00045 " piston to wall clearance .

 

[MTRHEAD]

Just curious if the new Wisecos are sized like you say or not. I have plenty of “older” Wisecos that were stamped 84.9. So I didn’t know if the newer ones that’s are over sized they call out piston size or bore.

I did find a brand new M08800 last night and it was about .006 undersized to 88mm so I think they call out bore size nowadays. Old days in some cases they did actual piston size

 

[Storbeck]

I think I have one I can measure after work if I can remember. I'm not super sure how old it is I bought it off of ebay maybe a year or so ago, but it's a data point.