why are there s header pipes?

[400exrider989]

if the 400ex is single cylinder then why is there to pipes running on the motor?

thanks

Originally posted by 400exrider989
if the 400ex is single cylinder then why is there to pipes running on the motor?

thanks

It uses 2 small holes instead of 1 big one. I dont think theirs a reason.

[400exrider989]

ok thanks thats what i thought because i looked at a bore kit and there was only one cylinder so i thought it was twin cylander thanks for responding

[440exroost1984]

It has to do with the design of the 400ex engine. Simply it has to exhaust ports.

[wilkin250r]

Multiple small exhaust ports are often easier than one single large port. The increased port area will improve top-end performance, allowing the engine to breath better and allow it to rev higher.