Upgrading your Harley with a new cam is often referred to as Stage 2 upgrade and is a step in the right direction to achieving greater performance.

If you have not already upgraded your bike to 'Stage 1' (Free-breathing air cleaner, exhaust, etc.), be sure to check out our previous article entitled Harley Stage 1 Upgrade before proceeding with a Stage 2 cam upgrade.

Selecting a cam can be a difficult decision given all of the information and conflicting opinions available. Often Harley riders choose a cam based on horsepower numbers, a huge mistake which can result in a decline in performance. Before selecting a cam it is important to consider riding style, bike type, and components that will provide the best combined performance.

As a general rule of thumb, heavy bikes requires a cam with more low-end torque. Big HP numbers are of little benefit for touring or 2-up riding on a heavy bike. Those with lighter bikes and typical street riding should opt for a cam that produce good low to midrange torque. Remember that while horsepower is good for bragging, torque is felt in the seat of your pants. It is not uncommon to smoke another rider off the line whose cams produce higher numbers on the high end.

Rule of thumb #2: Cams can be divided into 3 power range groups.

Low end: Cams with a duration of less than 235.

Mid range: Duration range of 235 to 250.

Top end: Duration of 260 or greater.

Cams in the upper mid to top end range with greater than .500" of lift require head work and higher compression. Therefore, I highly recommend consulting a qualified shop before making such a cam choice since this is not considered a "bolt-in" application.

A comprehensive list of cams for each model type shall be posted on the Harley-Performance site. Cam brands vary and the buyer should select carefully, since there are variations based on induction (carb of injection) and cam drive type (chain or gear). If you have the dealer install your new cams then you may be limited to Screamin' Eagle. Otherwise I recommend Andrews and Crane cams for both EVO and TC88 applications.

Ken's personal picks. The following cams produce healthy midrange torque and can be bolted in without any major modification.
EVO Big Twin - Andrews EV27 or Crane Fireball 310
Twin Cam 88 - Andrews TW37
Twin Cam 95 - Andrews TW44
Sportster - Andrews V2 (1986-90)
Sportster - Andrews N2 (1991-99)
Shovel - Crane 298 or H298

For a more detailed description of cams and specifications please be sure to look for the upcoming article posted at Harley-Performance.com