2 Strokes Down Under

You can go up to 0.8mm on plating so effectively you could go reduce bore size by 1.5mm.
Seizures are not that much of a problem , excess ali comes off with hydrochloric acid and a cotton bud.

good info, thanks, i would feel more comfortable with a .5mm o/s than 2mm, one more question, can the plating be bored out at all or is it to hard? if it was damaged would the whole process need to be repeated? thanks

errrrrm that's the idea of plating YOU DON"T NEED TO REBORE IT JUST REPLACE THE PISTON WITH ANOTHER THE SAME SIZE.

thanks for that, didnt know that but i sure do now,cheers

I have been running 2mm oversize in my RD370LC race bike with Wiseco pistons with no problems. I would be happy to run 2.5mm with the Nickosil plating.
I never have seizures. I run Penrite Hyper 2stroke at 24:1 and drill the pistons either side of the exhaust port.

Ohhhhh dear

350 cc + 5% = 367.5cc
66mm bore X54mm stroke= 369cc


Secrets safe with me

No need to keep the secret.
From memory, the 370 is the bike that Mark races with the bigger capacity bikes, so it's actually well under the limits.

Throw that stroker crank in then

I make sure my bikes are completely within the rules.
The 250 is 1mm os.
The 350 is 1mm os.
The 370 is 2mm os.

I knew that just shit stirring

No worries. Pity I can't afford that OW31 replica cylinder.