Bicylce-Engines expansion chamber

bairdco

a guy who makes cool bikes
Aug 18, 2009
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living the dream in southern california
Once you tune your engine, the basic x chamber should have a 6" OD belly, with the appropriate diffuser and convergent cones. A KTM 50-80 pipe is about right, but you have to cut and weld to make it work.

I've yet to see a pipe that's not just a re-purposed pocket bike pipe that actually works.
 

kelly dean

Active Member
Oct 3, 2019
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kentucky
I've got one as a budget pipe its better than stock. I found with mine that the flange over lapped the pipe by quite a margin and dremeled that out to open it up