Published on March 4th, 2011 | by Joe0
HMF Yamaha Raptor 125 Exhaust Systems and Engine Kit
(2011) Yamaha Raptor 125
We brought in a customer’s Yamaha Raptor 125 for full research and development on an exhaust system. After development and endless dyno testing, HMF came up with a Slip On and Full System for the Yamaha Raptor 125.
Price: S/O-$289.95 | FULL-$339.95
Series: Performance and Competition
Note: Because of the Smaller CC engine, the Competition Series does not feature the Tri Max Core. It has the Performance Series core. Upgrading to the Competition Series is purely aesthetic.
Colors: Black, Blue, and Polished
Model Code: 4167
We tried 4 different head pipe designs along with 3 different silencer designs before coming up with a combo that made good power across the board.
By simply bolting our full system up to the little Raptor we saw a 15% gain in power. After seeing how choked up the intake side is, we removed the air box lid, backfire screen, and added a K&N filter with Outerwear. We found the stock carburetor was not up to the task of supporting the increased flow of the new exhaust and air box/filter modifications. The Keihin PE28 Carb was dropped in place of the original. After some fine tuning, we saw a 30% power gain over stock.