400ex jetting

[Flatwoods Flash]

I have a 400ex that is being rebuilt. I'm getting a Wiseco 10:1 piston and it will be bored to probably a 406. Also I will be runnin with the baffle out of the stock muffler. How much effect would this have on my jetting. What would be some good sized jets to try?

[Chino886]

Originally posted by Flatwoods Flash
I have a 400ex that is being rebuilt. I'm getting a Wiseco 10:1 piston and it will be bored to probably a 406. Also I will be runnin with the baffle out of the stock muffler. How much effect would this have on my jetting. What would be some good sized jets to try?

start in the 150-160 range, I don't know what elevation you are at. I have a JE 10.5, Stage II cam, Sparks x-6 full system and I am running a 165.