[saki800]

I'm think of putting straight pipes on my Vulcan 800. I'm told that if I do so I'll have to reject the carburetor. Others have said no that rejetting isn't always necessary. So how do you know? Does it have something to do with whether the after-market pipes have baffles? I'd prefer not to rejet but I want the straight pipe sound.

 

[hot_shoe_cv]

If a pipe is doing the job it's supposed to, which is to provide more exhaust air flow, re-jetting is required to restore the fuel/air balance. If the pipe does not increase the flow, naturally re-jetting isn't necessary. The best way to find out without putting the bike on an engine analyzer would be to do a plug read using a brand new plug. After a high speed test ride pull the plug and read it for color.