What size main do i need to go to on a white brothers e-series pipe(no headers) i got 160 now? I think i need 165 but not sure

 

with only a pipe I was at a 155. with the pipe and K&N filter I went to a 160. I left the other at the stock 38. I'd leave it there until you do more. If you race it get a rev kit.

 

I went with a 160main with the airbox lid off and a K&N filter, I also moved the needle down one spot, This seems to work good, I am getting some bog at the top end but I dont know if its the mods or the rev limiter. Its definetly running better Im pretty sure its the rev limiter, I will know soon Im gonna get the white brothers rev box.

 

I've been pleased with the wb rev box. It really helps in climbing and I don't know about most but I found 58 mph before I went to 5th gear and no k&n kit yet.