Supertrapp Dyno Test


The Supertrapp is a popular exhaust system on Harley Big Twins and XL's alike. We offer Supertrapp systems and we've seen many examples of our customers getting great results when using them.


Often we get asked about how many discs to use. Every engine combination has the potential to be a little different, but we went to the trouble of dyno testing disc packs from 12 to 26 on our '04 Sportster, which is a typical mildly modified street bike. Here are the results of that testing:



All of these pulls were done on the same day, on the same bike, as close in time to each other as possible. As you can see, adding discs helped midrange and top end power in all cases, and never lost any bottom end power!


In general, we like this exhaust, it diffuses well with lots of discs in it and gives a good wide powerband.


We also did a few pulls with the end cap and discs removed, just to see what it did. Here we compare the best one with the 26 disc pull above:



As you can see, you need the discs!


Supertrapp systems are readily available from NRHS, even if they're not on our web site right yet. Give us a call at (303) 833-4500 and we'll fix you right up.


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