perf pipe and jetting--leaner or richer?

[uperjim]

My son just put Aaen quad pipes on his V-max4 and he has a sheet from Aaen that shows you start with the factory jets and lean from there. That just plain does not sound right to me. I always thought you have to go richer not leaner with a pipe. Anyone have any experience with this and better yet can you explain why the pipe affects jetting?

Thanks a ton! We need snow!!!!