If you've been looking into ways to wake up your Milwaukee-Eight or Twin Cam engine, you've probably heard more than a few people raving about feuling cam kits. It's one of those upgrades that consistently tops the list for Harley riders who want more than just a loud exhaust. Let's be honest: stock bikes are great for cruising, but they often feel a little "choked out" from the factory due to emissions standards and general mass-production limitations.
Swapping out your cams is essentially giving your motorcycle a fresh set of lungs. But the reason people gravitate toward Feuling specifically isn't just about the bump in horsepower—it's about how complete their packages are. Instead of hunting down individual gaskets, bearings, and bolts from five different websites, these kits put everything in one box so you can actually get the job done without a mid-project trip to the parts counter.
Why These Kits Make Such a Huge Difference
The heart of any internal combustion engine is the camshaft. It controls when the valves open, how wide they open, and how long they stay that way. When you install one of the feuling cam kits, you're fundamentally changing the personality of your ride. You aren't just adding a few horses; you're shifting where the torque sits in the RPM range.
For most of us, we want that "get up and go" when we're merging onto the highway or passing a slow-moving truck. Stock cams tend to be very linear and, frankly, a bit flat. A performance cam kit replaces those dull characteristics with a much more aggressive profile. You'll notice the bike pulls harder, sounds deeper, and reacts much faster to your right hand.
Beyond the power, there's the reliability factor. Feuling has built a massive reputation for their "system" approach. They don't just think about the cam lobes; they think about the oiling system, the lifters, and the stability of the valvetrain. If you're going to open up the chest of your bike, you might as well put the best parts back in.
What Actually Comes in the Box?
One of the most annoying things about engine work is realizing you're missing a single O-ring halfway through the teardown. Feuling cam kits are popular because they are curated to prevent that exact headache. Usually, you're looking at a "Race Series" or a "HP+ Series" kit, and the contents are pretty impressive.
You get the camshafts (obviously), but you also get the high-flow oil pump and the high-volume cam plate. These two components are arguably just as important as the cams themselves. The factory oil pumps, especially on earlier M8 models, had some known issues with "sumping" or inconsistent pressure. Feuling's pump moves more oil and creates better scavenge pressure, which keeps the engine cooler and better lubricated.
Then you've got the lifters, the cam installation kit (which includes all the necessary gaskets and bearings), and sometimes even adjustable pushrods. Having everything designed to work together means you won't run into clearance issues or weird harmonic vibrations that happen when you mix and match brands.
Choosing the Right Reaper Cam for Your Style
Feuling names their cams the "Reaper" series, which sounds cool, but you need to know which number fits your riding style. It isn't a "bigger is always better" situation. If you pick a cam designed for high-RPM drag racing but you spend all your time touring with a passenger and luggage, you're going to hate the way the bike feels at low speeds.
- The 405 or 465 Cams: These are usually the "sweet spot" for most riders. They provide a massive boost in low-to-mid range torque. This is what you want for stop-light-to-stop-light riding or cruising through mountain twisties. You get that immediate grunt without having to scream the engine out to 6,000 RPM.
- The 508 or 521 Cams: These are for the guys who want a bit more top-end. If you like to ride fast and you don't mind dropping a gear to get into the power band, these offer a more aggressive lope at idle and a serious rush of power once you get moving.
- The 592 and Beyond: Now we're talking about big-bore builds. These require high-lift valve springs and usually some head work. It's a total blast, but it's definitely more of a "performance first" setup.
The Oil Pump and Cam Plate Connection
I can't stress enough how important the oil pump and cam plate are in these feuling cam kits. A lot of guys try to save a few bucks by just swapping the cams and keeping the stock plate. It's a gamble. The cam plate acts as the "brain" for your oiling system, and the stock ones are often made of cast material that can warp or wear unevenly over time.
Feuling's plates are machined from 7075 billet aluminum. They are incredibly stiff and hold their tolerances way better than the factory parts. When you pair that with a high-flow pump, you're essentially bulletproofing the bottom end of your engine. It ensures that even when you're pushing the bike hard on a hot summer day, your top end is getting a steady, pressurized stream of oil. It's cheap insurance for a very expensive engine.
Dealing with the Chain Drive vs. Gear Drive Debate
If you're working on an older Twin Cam engine, you have to decide between a chain drive or a gear drive setup. Most feuling cam kits offer both options.
The chain drive is what the factory uses. It's quieter and a bit more forgiving if your crankshaft has a tiny bit of "runout" (meaning it isn't perfectly straight). Feuling's modern hydraulic tensioners make the chain drive very reliable, so don't feel like you're taking the "cheap" route by sticking with chains.
Gear drives, on the other hand, are the gold standard for timing precision. They eliminate the chains and tensioners entirely, which means there's nothing to wear out. They also give the bike a distinct mechanical "whir" that sounds like a race machine. The catch? Your crank runout has to be nearly perfect (usually less than .003) for gears to work. If your crank is wobbly and you throw gears in there, you're going to have a very bad, very expensive day.
What to Expect After the Install
The first thing you'll notice after installing one of these feuling cam kits is the sound. Even with the same mufflers, the exhaust note becomes crisper and more rhythmic. It loses that "muffled" sewing machine sound and starts to sound like a proper V-twin.
But the real magic happens when you let the clutch out. The bike will feel lighter because it takes less throttle to get it moving. Overtaking cars becomes a breeze—you don't always have to downshift two gears just to get around someone. You just roll on the gas and the torque pulls you through.
One thing to keep in mind: you must tune the bike. You're changing the air/fuel requirements of the engine significantly. If you just slap in a cam kit and ride off, the bike will likely run lean, get too hot, and pop on deceleration. A good flash tuner or a trip to a dyno shop will ensure you're actually getting the power you paid for.
Final Thoughts on the Upgrade
Is it a cheap project? Not exactly. Between the kit itself and the labor (if you aren't doing it yourself), it's an investment. But in terms of "bang for your buck," feuling cam kits are hard to beat. You're getting better performance, better oiling, and the peace of mind that comes with high-quality billet parts.
If you're tired of your bike feeling a bit sluggish when it's loaded down, or you just want that classic Harley lope and power, this is the way to go. It transforms the riding experience from "pretty good" to "I never want to get off this bike." Just make sure you pick the cam profile that matches how you actually ride, not how you wish you rode, and you'll be smiling every time you hit the starter button.