A new pipe is high up on most owners’ list of desired modifications. Swapping exhausts is usually pretty easy, but the job will vary based on the style of bike and the number/layout of the cylinders.

As much as we like the 5.9L Cummins powerplant, the stock exhaust manifold is constrictive and contorted, interfering with the flow of gases to the turbo and downpipe. That, in turn, can produce the ...