125-200cc What pistons interchange on Wr125?

let us know if its any better
if you can ride
(its too hot here at themoment )
did you check the squish ? is it easy to do - squashing solder?
quick explaination please ?
I know there is a link here on this site somehwere

a bit of topic - attached is a pic of my recently removed piston next to a wiseco fbf piston - not sure iof they are same as normal wiseco pistons
would the darkened sides be from worn rings ?
View attachment 7488

http://www.rb-designs.com/squish-band-test.htm

My stocker has a coating on mine. I think that's what your meaning?

No - if you look at the original piston and parts of it below the rings are blackened
I believe that this is a sign that the rings were worn and allowed some of the combustion to escape to sides of piston

It is really hard to tell with that pic. I am getting old and my eyes aren't what they used to be.

Sorry Darin I see what you mean now. OEM pistons have a grey coating thats worn down in parts
Walt my eyes are going too dont worry
Is B the size of the piston ? anyone know what size differences are?

whats the purpose of the "holes" in the side of the two non oem pistons??

Those are cooling holes for the exhaust bridge. The oem pistons have them too.

I think he meant above the wrist pin.

correct ... the big soop looking deal .....

Mark has gone the whole hog which i am surprised about as he has said he is more of a trail rider . I guess we always want that little bit more.
Can you really tell a bike performance with one ride though ? Bikes run best at certain times- conditions.
Why was Ryans bike going so well?

My bike was running a little better on pump with the stock head then it was yesterday. I need to spend some hours jetting now. But it was pouring rain all day so I just left it alone.

Even with .3mm taken off the head it still only has 180psi cold so if I decide to stick with race gas I am having more head work done. If I can not get it to run a lot better though I will probably go back to pump, or maybe a mix.

I really do not need more power but I hope to get instant throttle response. It just makes the bike more fun to ride. I think a CR ignition might help there also.

Cr - ignition - yeh definately refer my other thread - I am considering buying a bike just for the ignition and to have spares