Higher Compression?

This may not have come up because I doubt many people have had the need to rebuild yet, but has anyone put in just a higher compression piston to see what the gains are? considering the bike doesn't ping even on 87, I'm sure we could run something like 13:1 instead of 11.8:1. I wonder how much of the gain from the big bore kits is from the compression alone.

Would a 77mm R1 piston fit?

To my knowledge R1 models from 2004 to 2008 have the same bore and stroke (77.0 x 53.6 mm) as the WR with a compression of 12.4:1

So it would theoretically "fit". Now if it actually works, who knows....

It sure would be interesting and a great project

Maybe someone knows more... I'll be keeping an eye on this

Thinner head gasket or shave the head?

somebody should be brave and try it out for the rest of us
my buddy runs busa pistons in his sv

See if it were a motor that gets torn down all the time, Id be all for it. As is, I feel the need to be super careful and not mess up its super reliability on a hunch. If it worked though, you could buy an aftermarket R1 piston and jump up to like 13.5:1 compression (if you live in a 93 octane area) for ~$130. More power across the board Especially low end and midrange.

Only question really is if the cylinder can handle the extra compression

is it build tough enough? Although since it's doing fine for some people with turbos I don't think there should be a problem...

If the bike keeps going like it has, I might give this a try in 15 years or so when the engine needs a rebuild

Gotta love the crazy reliability

The R-1 piston will fit, but the valve releafs are not the same.
J.E. makes a 13:1, off the shelf for the WR250R, you can buy. $190.00.

By my math 13:1 would get us about 1.2 - 1.4 hp. Dont think id bother for less than 2hp which is about what 13.5:1 would give. Actually the more i think about the numbers the more fruitless it seems lol.

Sounds like a lot of work for the gain & if it compromises the reliability of the WR then it becomes a hassle when repair time rolls around too soon. I think doing the free airbox mods etc., would be more bang for no bucks.