Harley-Davidson Camshaft Specification Selection Criteria

General Cam selection guidelines

Estimated Maximum Intake Duration
Performance Note: We find that few street bikes actually need compression ratios higher than a nominal 9.5:1 with proper engine components and good tuning. With a good flowing set of heads, engines like this can easily make over 1HP/CID and 1+ft.lb./CID with little worry about overheating, detonation and longevity. This means a TC95/96 engine is capable of 100HP/110ft.lb. torque without having to 'go crazy' with high compression and wild cams.

These numbers serve as broad guidelines and can generally be considered the "top end" of selection criteria. There is little risk in installing more conservative components, but a big risk in using more aggressive parts. Keep this in mind as you select components for your engine. There are many components to building a performance engine that effect how the final product will run. Quality of assembly, proper tuning and matched components are very important. When in doubt, use the less radical part.

Typical Bolt-in Camshafts
EVOLUTION

TWIN-CAM 96/103/110 For 2007 and Later Bikes
The gearing of the 2007 and later bikes really prefer cams with very low power bands. Cams that optimize power under 4500 RPMs tend to be much better suited for these late model bikes unless you change the primary or final drive gearing. We highly recommend giving up maximum HP in favor of a lower, broad power band under 4500 RPMs for these bikes.

TWIN-CAM 88/95/103 For 2006 and Earlier Bikes