Let's talk about exhaust, straight pipes, baffles, bogging, and back pressure

[TwoManyXS1Bs]

JD750ace, thank you, that article portrays the agony of `70s tuning. We were being hit with various combinations of bikes with various components and customer 'already-cut-where-I-want-it' pipes, AND these guys expected the standard $12 tune-up would fix it. We just didn't have the formulas/answers back then...

 

[shotgunjoe]

I think the consesus was that open pipes work... with tuning. Just throwing on a set of free flowing mufflers wont eliminate the need to rejet your carbs. The free'er flowing headers alone facilitate the need for a rejet.

Just sayin...

 

[lidirtrider]

Another option that I've seen NOBODY utilize might be the chrome muffler tips from VW Beetles. These are actually mini mufflers, straight through but with a louvered core backed by some sort of sound deadening material. To me, it seems they may be ideal, giving you all you're after - increased length, back pressure, and some muffling.

Thats exactly what i have on my 75 cafe project. For now I just some clamps to keep em' in place. The original mufflers were just hacked off at the footpeg. The VW tips, are just like you said, stright through but with some sort of honeycomb core. The best part is they are almost the exact diameter of the stock headers so it looks like straight pipes. They have a nice mellow tone at idle, but they really growl when I open it up.