Camshafts

To help you make that arm-jerking torque and horsepower you seek, NRHS offers a collection of the BEST cams available!

Camshafts are a key component for your engine, and your choice in cams has the potential to make or break your project. But it's easy to get overwhelmed while shopping for cams, because there are so many choices available. What's a person to do?

Successful camshaft selection starts with an understanding of the interactions between the intake system, the flow characteristics of the heads, the bore and stroke of the engine, the compression ratio, and the exhaust system, all tied together with a master plan. But beyond that, it also requires experience. Not every cam grind that looks good on paper will actually work well for you. This is because cam specs alone don't tell the whole story, they represent just a handful of dimensions on a highly complex shape, and they don't give nearly enough information about critical parameters such as valvetrain dynamics.

Fortunately, NRHS has extensive experience with many grinds in many applications; we build lots of street and race motors and we help literally hundreds of people each year with their personal projects. On this page, we've put together a list of the cams we have the most success with in each type of application. In particular, these cams work exceptionally well with our head porting services. If you are in doubt or confused about which grind is appropriate for your application, please do not hesitate to call and speak with a performance consultant.

Except where noted, these cams are not “bolt-in”. Installation requires careful checking of various clearances as well as valve springs that are appropriate for the application. Also, we highly recommend roller tip rocker arms for cam lifts above .550”.

Twin Cam Camshafts

In the Twin Cam line, we offer quality grinds from both S&S and Red Shift. We've had tremendous success with both brands.

For a mild, bolt-in grind that doesn't need a lot of spring pressure, the stock cam chain arangement is fine. However, at NRHS we feel a gear drive is essential, not optional, on high performance Twin Cam grinds with extra overlap and high spring pressures. Besides being able to handle the increased spring load reliably, the superior control of the cam timing offered by a gear drive becomes much more critical in high performance applications because piston to valve and valve to valve clearance are generally being pushed harder. This is not  a place where you want to cut corners! A failure will take out a lot of expensive hardware. Gear drives also reduce the torsional load on the cam bearings as well as significantly reduce friction. It's a better setup all around. All gear drive cams are supplied without gears, see below for gear drive components.

S&S TWIN CAM GRINDS

S&S Twin Cam grinds offer exceptional torque and horsepower for all applications.  The 510 is the best Twin Cam bolt-in we've found. The high-lift/narrow 570G is terrific for arm-jerking, tire shredding torque. The 585G is a terrific all around street grind. And the 625G & 640G grinds produce some truly impressive horsepower with our Stage 3 head work. As with everything we carry at NRHS, we carry the S&S line of cams because they work!

Note:  Due to S&S policies we cannot post prices on the internet. Please call us for prices.

* - fits 2000 and later Twin Cam, can be fitted to 1999 model if the HD 2000-up style splined rear cam sprocket is used

RED SHIFT TWIN CAM GRINDS

Red Shift also offers some terrific Twin Cam grinds.  Red Shifts are known for their leading edge lobe profiles which produce tremendous power and torque while maintaining dynamics that allow the valvetrain to live. We've found these cams to be an excellent match to NRHS head work.

GEAR DRIVES AND INSTALLATION KITS

Evolution Big Twin Camshafts

NRHS has extensive experience at making big power with the venerable Evolution Big Twin. We've listed our favorite cam grinds below.

Note that in 1992, HD changed the cam bearing from a Torrington style with 29 rollers to a new INA bearing with only 19 rollers. Many of these cheaper INA bearings have been known to fail, particularly in high performance applications. We highly recommend changing this bearing to the older Torrington whenever you change the cam in an Evolution Big Twin.

CRANE EVOLUTION BIG TWIN BOLT-IN GRINDS

For bolt-ins, we prefer the Crane Firebolt lineup, for a couple of reasons. First, Crane offers this line with or without the drive gear. Re-using your existing drive gear saves money as well as maintaining that perfect fit your bike came from HD with. Moving your old drive gear to your new Crane cam is not difficult to do with a common hydraulic press and Crane even includes a little kit and instructions to make it easier. If you're uncomfortable with this job, send us your old cam or old drive gear and we'll move it for you at no charge. The other reason we like Crane Firebolt bolt-in cams is that we've found they perform comparably to other popular bolt-ins and yet have much better valvetrain dynamics than most. This is especially important on the Evolution Big Twin due to the extra pushrod angles and the marginal oiling of the front exhaust tappet.

RED SHIFT EVOLUTION BIG TWIN GRINDS

For higher performance Evo Big Twin grinds, we're partial to the Red Shift line. Red Shift cams work exceptionally well and unlike many cams in these ranges, Red Shifts have excellent valvetrain dynamics that provide for a long life.

EVOLUTION BIG TWIN CAM BEARINGS

Evolution Sportster & Buell Camshafts

91-04 Sportster and 95-02 Buell

Cam gear fit can be an issue in Sportsters and Buells, particularly 1999 and older models. HD literally had 7 different sizes for each gear, including the pinion gear, and each engine coming off the production line got a combination of gear sizes specific to that engine. Gears were matched in this manner to minimize noise.

When changing cams in one of these motors, it's important to check the cam fit and make sure in particular that the gears turn freely and do not bind. Having gears a little bit loose is okay, you'll get some clatter but it doesn't hurt anything. Too tight, however, is a problem, it can cause localized heating of gear teeth and that can cause a failure. Aftermarket cam sets are  supplied on the loose side so they will work in the majority of engines, but always check. The 91-99  pinion gear we sell is the "yellow" gear and is the smallest gear available.  It will work will all course pitch cam sets but it may be a little noisier than stock.

In the 2000 model year, HD changed to a high contact ratio gear cut between the pinion gear and the #2 cam and eliminated the need to fit this connection. In 2001, this change was propagated to all of the connections between the cams. These later style cams can be installed in earlier engines by using a late model high contact ratio pinion gear (see below). Likewise, cams with the older gear cut can be installed in later engines by backdating the pinion gear.

SCREAMING EAGLE EVOLUTION SPORTSTER GRINDS

In milder Sportster/Buell engines, we have tremendous success with Screaming Eagle cams. The Screaming Eagle bolt-ins (stock in many Buells) are the best bolt-in grind we've ever tested in these engines. Moving up the scale, we have repeatedly made 104-107hp with SE .536's and Stage 3 headwork in 1250 kits. Both of these cams work fine with stock pushrods, lifters, and rockers, too, keeping the costs down. All things considered, these cams perform well and are a terrific value.

The new SE "E" grind is a terrific high-torque grind, relatively narrow with high lift and exceptional valvetrain dynamics. Note that this grind is a bolt-in for 2004 models but in 2003 and earlier models, better springs are required. Also note that it has a .050 smaller base circle than the 2003 and earlier grinds, consider this when calculating ideal pushrod length. This is the same cam grind (but not the same set of cams) that comes in new Buell XB models.

New for 2005 is the SE .575 lift cam set for XL's. Our testing has shown this to be an excellent grind for street performance use, with the potential for the same or more power across the rpm range as compared to the SE 536, but like the SE 536, it's valvetrain dynamics are good enough for an everyday street motor, without the need for excessively high spring pressures and the expensive supporting cast of valvetrain components that goes with it. See our Tech pages for more info.