View Full Version : Universal/3M dirt bike muffler

06-01-2008, 08:13 AM
I have just fitted a 2:1 header pipe to my old 89 1200 xl sportster and now need to find a suitable muffler. I intend to use a short 45 degree stainless bend to slightly redirect the exhaust out and up to clear the swingarm. I was thinking about fitting one of your 3" black dirt bike mufflers on the end. The question is will it have enough flow for my bike. I'm running andrews cams, HSR42 carb and a few other extras. The exhaust bore after the collector (Y) is 2", so I was looking at the 2" inlet model, 317-2000.
I would also like to know the length and the weight of this model.
Many Thanks

06-02-2008, 07:19 AM
The core assembley in the 3M units is 1.75" ID. I would highly reccommend the 4" Universals which will provide a 2" core with a 2" inlet. Take a look at the S/C or 4" Aluminum Racing Series.

06-02-2008, 12:12 PM
Thanks for that.
I was looking at the SC Elite, either 433-2011 or 433-2017, but was wondering what effect the length of the muffler has on performance?

06-04-2008, 07:05 AM
Sound levels (larger/quieter) are probably the most noticed effect muffler length has in a street application.

05-18-2011, 10:07 PM
This one will handle a Sportster motor just fine: