Hey guys I'm new here and have a question for the experts. I have a bassani road rage (model 1D12R) I just installed a week ago. Well so far I've drug the lower exhaust pipe across the pavement and now I'm thinking about switching to the short upswept road rage (model 1D5250). The biggest question of doing the switch is I have stepped head pipes on the pipe I have now but the short upswept does not have stepped headers. Now I do understand the need to have stepped headers in a 2-2 system with out a crossover pipe but is this the same for a 2-1 system?

 

Had to think on this for a bit. While a 2>1 design scavenges the spent gases more efficiently, resulting in improved velocity of the gases exiting the head, there still is the issue of reversion to deal with, although, at least theoretically, a well-designed 2>1 will reduce the amount of spent exhaust gases remaining in the head pipes to revert back into the combustion chamber on the intake stroke.

Looking at two of the highest performance 2>1's out there, the D&D Fatcat and the Thunderheader, both use purposely-designed techniques to reduce reversion. The Fatcat uses stepped primaries and the Thunderheader uses a "anti-reversion cone" at the tip. This would imply that there are real benefits to using stepped primaries on a 2>1 pipe to reduce reversion, just as with a 2>2.

 

Thanks Dynawg1! I was thinking the same thing just wasn't sure if I was right on my hunch! I'm a little disappointed the pipe scraped on me. The last thing I wanna do is raise the height on the back of bike. (I have a 2015 Low Rider and love how the back end sits.) But anyways I would like to stick with a 2-1 system that will accommodate and preform well on the mild build I plan on doing later to the bike without breaking the bank!