Will it Hurt My Harley Davidson If I Put New Exhaust on Without a Fuel Pack?

Using a Fuel Pack

A Fuel Pack or a similar Electronic Fuel Injection control will add additional fuel compensate for the increase in the flow of air through the motor and exhaust. This will improve the motor's performance and reduce overheating.

Exhaust Changes without a Fuel Pack

It's possible to make changes to the exhaust system without making the appropriate changes to the air/fuel ratio. However, the increase in air flow will generate more heat that could cause internal damage under extreme conditions. Additionally, the motor's performance could be adversely affected and create a distinct popping sound at idle or during deceleration.

Bottom Line

Installing a Fuel Pack, or EFI controller, is always recommended when changing exhaust systems to prevent a loss of performance. If left unchanged, the excessive heat caused by increased air flow can cause permanent damage to the motor. Ultimately, the cost of an EFI controller is minimal compared to the cost of rebuilding an overheated motor.

References

• "The Professional Motorcycle Repair Program"; Professional Career Development Institute; 1995