mx top end

[8secnotch]

I have a 05 that has a pretty much stock engine except for a full pipe and a filter for now but I have a 02 CRF cam and I was debating on what piston to go with. I was going to get je 13.8:1 two ring race piston but was wonder if that would be too much for a stock head so I was thinking about going with a je 12.5:1 piston and a thinner cometic head gasketto up the compression just a little. I'm looking for something thats runs good but still be reliable.Which set up do you think would benifit me. I also wanted to tell ya that I'm going to do the head next. Another question I have is how often do you guys change out the timing chain?

[exrider12]

Big question.. Race gas or no race gas?

[eastside 400]

if you are alright with running race gas then go with the highest compression you can. I like the venom 14.25:1 pistons, its a custom built CP, the shelf CP race piston is really good too. you cant really go wrong with any of the top piston makers, Wiseco, Je, CP. if you dont want to run race gas then keep it around 12.5:1

[8secnotch]

It would be race gas only and how much of a difference does head work and oversized valves make?

[BlaineKaiser450]

All seperate, you won't see much increase but a strong motor with a cam, high comp. piston, good porting, and valves is a very big improvement. I like CP or DRG pistons btw

[wckedclownz69]

im running cp 12:1 with hot cams stage 2 and hot rods crank... i love it only run 93 in it too..