The Honda Clone platform has seen significant development over the last decade. New engine blocks, improved cylinder heads, higher quality carburetors, and stronger internal components have all contributed to increased performance and reliability. However, there is one component that has not evolved nearly as much alongside these advancements—the camshaft.
Most aftermarket performance components for the Honda Clone are designed specifically to improve engine performance for kart racing. These components are typically developed with particular engines and racing classes in mind. For example, camshafts such as the Mod 2 for Cheater Stock, the 255 for the Briggs Animal, 275 lift cams for F200, and the .308/MOD1 for Limited Modified are all designed around specific rule sets and performance goals. Beyond those, most other camshafts tend to fall into either low-lift or high-lift open modified race cams.
A key point often overlooked is that many of these camshaft designs were originally developed for the Briggs Animal engine, not specifically for the Honda Clone platform. While the engines share some similarities, they differ in several important areas such as cylinder head design, bore and stroke dimensions, and piston speeds. These differences affect how a camshaft behaves in each engine.
Because of these differences, a camshaft designed around the Briggs Animal may not always perform optimally in a Honda Clone engine. The way airflow behaves through the head, how quickly the piston moves through the stroke, and how the engine is modified all influence how the camshaft ultimately performs. On top of that, racing class rules dictate what modifications are allowed, which further influences camshaft selection.
In most racing applications, camshafts are designed primarily to maximize performance at higher engine speeds. Even in classes where porting and valve size are restricted, camshaft design tends to prioritize top-end horsepower in order to maximize on-track performance.
However, the reality today is that Honda Clone engines are no longer used strictly for kart racing. The market has diversified significantly over the past 20–25 years. Clone engines are now widely used in minibikes, off-road karts, recreational vehicles, marine applications, and utility vehicles. Even within kart racing itself, the variety of classes and track types has increased dramatically.
Because of this shift, the camshafts available on the market today are not always compatible with the goals of many modern engine builds—especially when combined with the wide range of upgraded components now available.
The Modern Combination Problem
One of the key issues we need to address involves the typical engine combinations being built today.
Many recreational and performance engines are now equipped with carburetors ranging from 22mm to 26mm bore sizes, with 20–24mm venturis. In most cases, these carburetors significantly outflow stock cylinder heads.
However, aftermarket cylinder heads such as the Shredder and Wildcat WC946 have made higher-flowing heads more accessible than ever before. More importantly, these cylinder heads have additional material in critical areas that allow the cross-sectional area of the ports to be increased during porting. This enables significantly higher peak airflow numbers.
While this additional airflow can improve peak horsepower, it can also begin to negatively affect low-speed performance due to lower port velocity—especially when combined with aggressive ignition timing, larger exhaust systems, and larger carburetors.
In many cases, these combinations actually produce less horsepower and torque at lower RPMs compared to milder engine builds such as typical Stage 1 setups with stock cams. When we say lower RPMs, we are generally referring to below approximately 4500 RPM.
For many racing applications, this may not matter because the engines rarely operate below that range. However, in 4-cycle sprint kart racing, it is not uncommon for engine speed to drop as low as 3600 RPM in rpm limited engines, and sometimes even lower depending on track layout.
This creates a situation where an engine that looks impressive on a dyno sheet may actually perform worse on track due to poor low-speed recovery.
The Hot Rod Comparison
The situation is very similar to what happens when someone installs a large, lopey camshaft in a street car or truck.
When installing an aggressive camshaft in an automotive engine, the cam manufacturer will typically recommend installing a torque converter with a higher stall speed. Without doing so, the vehicle may actually lose acceleration and become less responsive at lower engine speeds.
Unfortunately, much of the aftermarket minibike and karting market has focused almost entirely on peak horsepower numbers as the primary indicator of engine performance.
In reality, this often leads to disappointing results for customers.
Just like those large automotive camshafts, engines built with aggressive cam profiles may not perform well unless the entire combination is optimized. Many customers continue using a clutch or torque converter with the factory stall speed of roughly 2200–2500 RPM, while also making no adjustments to gear ratios that could improve acceleration.
As a result, the engine spends a large amount of time operating below the optimal RPM range of the camshaft.
This is one of the main reasons customers sometimes find that their new performance engine is no faster—and occasionally even slower—than their previous setup.
Our Approach: Improving Average Power
One of our primary goals was to improve low-speed performance without sacrificing peak power. Instead of focusing solely on peak horsepower numbers, we focused on improving average power across the usable RPM range.
To achieve this, we designed three camshafts, each offering a different performance focus while maintaining a broad and usable powerband.
Each camshaft emphasizes a particular portion of the RPM range while still maintaining strong performance throughout the rest of the powerband. The goal is to allow engines to accelerate harder while others are still waiting to “get up on the cam.”
During testing, we found that these camshafts were not overly sensitive to minor combination changes and could still produce strong peak numbers when paired with the right cylinder head.
In many cases, we discovered that very little peak horsepower was sacrificed—if any at all. Peak horsepower is largely dictated by the cylinder head’s airflow capability. Instead, our designs helped maintain peak horsepower while significantly improving low-speed torque and average power, and in many cases increasing peak torque as well.
Of course, the exact power output will vary depending on your engine combination, but we work closely with customers to help select the camshaft that best matches their setup.
Reaper
The Reaper camshaft is designed primarily for larger displacement and higher compression engines.
As displacement increases, peak power generally occurs at lower RPMs because a larger cylinder volume requires more airflow to fill. Larger engines can often produce similar horsepower numbers to smaller engines but do so at lower RPMs, while also producing significantly more low-speed torque.
This can be seen in our testing with Red Beard’s Garage, where our milder 236–240cc engines produce similar horsepower but noticeably more torque than heavily modified 212–223cc engines.
The goal of the Reaper camshaft is to move the powerband higher for these larger displacement engines, allowing them to continue pulling strong at higher RPMs.
The Reaper can also help improve top-end power in more restrictive setups, such as engines using stock or near-stock carburetors, or engines with relatively small valves and limited port work.
While the Reaper still maintains a reasonably broad powerband, we generally recommend it for engines primarily set up for racing applications.
Reaper Jr.
At the opposite end of the spectrum is the Reaper Jr.
The Reaper Jr. is an extremely versatile camshaft designed to produce excellent low-speed torque while still improving top-end power over stock or other mild camshafts.
This camshaft responds very well to improvements in cylinder head and carburetor flow.
In more restrictive engine combinations, the Reaper Jr. can increase top-end power while also improving peak horsepower and torque. In engines equipped with higher-flowing cylinder heads featuring larger valves and larger ports, the camshaft helps maintain or even improve low-speed power.
For example, when used in our Wildcat 240 engine with a WC946-3 cylinder head (ported 31/25 valves with 26 lb springs), the Reaper Jr. produces one of the best average power curves from 2500 to 7000 RPM that we have seen.
Throttle response is also noticeably better throughout the power band compared to many camshafts currently available on the market.
Banzai II
The original Banzai camshaft helped start the .265 lift cam revolution. Shortly after its release, nearly every mini bike company began offering their own version of a .265 lift cam.
With the Banzai II, our goal was to further develop that concept while specifically improving low-speed performance.
The new camshaft produces the same peak horsepower—and in some cases slightly more—than the original Banzai, while also improving peak torque and average power across the entire RPM range.
The Banzai II serves as our “when in doubt” camshaft.
It falls directly between the Reaper and Reaper Jr. in terms of overall performance characteristics. While the Reaper Jr. may produce the strongest average power from 2500–7000 RPM, the Banzai II comes very close and can actually outperform it above approximately 3500-4000 RPM.
The Banzai II also produces more top-end power, which makes it a versatile option for applications such as sprint kart racing or recreational engines that spend more time cruising at higher RPMs with a slighly higher clutch stall.
In more restrictive engine combinations, the Banzai II may not make any less power between 2500-3500RPM when compared the Reaper Jr, or stock camshafts or worse losing power compared to bigger camshafts, while still producing stronger top-end performance
Choosing the Right Camshaft
To simplify the selection process:
- Reaper Jr. – Focused on low-speed performance
- Banzai II – Balanced mid-range performance
- Reaper – Focused on top-end power
In more restrictive engine combinations—such as those using stock or near-stock valves, ports, and carburetors—low-speed torque is rarely compromised. In these cases, the medium or high-speed camshafts can often be used to help balance power and torque.
However, as the engine combination becomes less restrictive with larger valves, larger ports, and larger carburetors, low-speed power can begin to suffer. In those situations, the lower-speed camshaft profiles help restore balance to the power curve.
Alternatively, a low-speed camshaft can also be used in restrictive combinations to maximize torque, making it ideal for applications such as towing, trail riding, or marine use.
On the other hand, high-speed camshafts are often best suited for highly modified racing engines, particularly in situations where RPM drops are minimal—such as oval track racing.
And if there is any uncertainty, the Banzai II provides a well-balanced compromise that delivers strong performance across a wide RPM range.
Improved Valve Control
Another significant improvement in our camshaft designs involves controlling valve motion at higher engine speeds.
A common issue with many camshafts—particularly many of the .265 lift cams on the market—is valve float occurring between approximately 7000 and 7500 RPM.
This appears to be the result of a combination of valvetrain harmonics and camshaft profile characteristics. Interestingly, once the engine exceeds roughly 7500 RPM, the valvetrain often stabilizes and the engine continues to accelerate normally.
We can clearly observe this behavior both on dyno charts and through air-fuel ratio data. As the valve begins to lose proper sealing, we see a temporary dip in power along with noticeable changes in the air-fuel ratio.
The issue becomes more pronounced as valvetrain weight increases, or when ratio rockers are used to increase valve lift.
One possible explanation is that many camshaft profiles were originally designed around the Briggs Animal engine platform, rather than the Honda Clone. Or, that these cams were designed for less than 7000rpms with a very aggressive profile.
The Reaper, Reaper Jr., and Banzai II camshafts were all specifically designed for the Honda Clone platform, which helps address these valvetrain stability issues.
If you'd like to learn more about each camshaft and see performance data, you can find detailed information on our website using the links listed below.
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