How much back preasure?

[luoma]

I have the classic exhaust from the CMW performance kit and am thinking about drilling out the baffle for more noise. I like a good loud bark out the tail pipe, but am concerned about altering performance in a negative way. I have drilled a few tiny holes already to help lean out the mixure (new carb ran way too rich).

[Kevin Mahoney]

Have your way with it. Drilling out the baffle will increase flow some and may in fact be a good thing. The key is to make sure that you re-jet the carb when you have settled on a configuration

[luoma]

Thanks, I think I will open it up a bit more. Even with no silencer, these bikes are not as noisy as the custom V-twins roaring up and own the road.

I think I've got the carb just about right. When I first installed it, it was very rich, si I moved the clip on the needle one notch. That seemed to help, but the plug was still a bit sooty, Not enough however to move the needle another notch, so I put a few 1/4" holes in the baffle by going in through the inlet side of the silencer. It's still pretty quiet and the plug is cleaner.