Yamaha Raptor 660 Exhaust Systems

Exhaust Description

The Yamaha® Raptor 660 is available as a Slip-On or Full System in the Performance and Competition exhausts.  Depending on the exhaust series, the slip-on system picks up 10-15% more horsepower, while the Full System adds an extra 5-10% more horsepower.  Riders will typically hear a 4-6dB increase in sound when compared to the stock muffler, however, the Competition Inserts and HMF Quiet Core can decrease those 2-4 dB.

Fits: (01-05) Raptor 660R, T, SET, YFM660RN

Fuel tuning is required learn more

Fuel Tuning is absolutely required when installing an HMF Exhaust on this machine. Failure to tune the engine can cause excessive damage to the exhaust system and engine, while voiding the warranty on your exhaust and possibly on your machine. (check with local dealer). See the tuning settings below for the proper fuel tuning solution on your machine.

Recommended Tuning - Stock Air Box
Left Carb: 145-150 Mikuni (or equivalent) Small
Right Carb: 150-155 Mikuni (or equivalent) Small
Needles on 3rd position

Recommended Tuning - Modified Air Box
Left Carb: 150-155 Mikuni (or equivalent) Small
Right Carb: 150-155 Mikuni (or equivalent) Small
Needles on 3rd position

HMF Basic Jet Kit Includes
140, 145, 150, 155, 160  Mikuni (or equivalent) Small

Resources

• Yamaha Raptor 660 Full System Installation Instructions
• Yamaha Raptor 660 Slip-On Installation Instructions