Motorcycle Cam Selection: Your Guide to Stage 2 Camshaft Upgrades

Thinking about a Stage 2 upgrade for your motorcycle? Upgrading your camshaft is one of the biggest performance boosters for your bike. But with so many options out there, choosing the right camshaft can quickly become overwhelming. Don’t worry—we’re here to simplify the process.

This guide will walk you through everything you need to know about motorcycle cam selection, from how cams impact your bike’s performance to understanding key camshaft specifications. By the end, you’ll have the knowledge to select the perfect setup to meet your needs.

What Is a Camshaft, and Why Does It Matter?

The camshaft is essentially the “brain” of your motorcycle's engine. It controls the opening and closing of the intake and exhaust valves, dictating how air and fuel enter and exit the combustion chamber. Even slight changes to a camshaft can dramatically affect your bike’s performance.

When designed correctly, a camshaft can improve:

• Torque for quicker acceleration
• Horsepower for higher speed
• Fuel efficiency
• Throttle response

However, choosing the wrong camshaft can lead to poor engine performance, rough idling, and even mechanical issues.

To make the best decision for your Stage 2 upgrade, it’s essential to understand the different aspects of a camshaft.

Key Factors in Motorcycle Cam Selection

1. RPM Range and Application

One common mistake is over-camming the engine, leading to lost performance in the RPM range you ride most. For example:

• If you primarily ride at low to mid RPMs (e.g., highways or touring), choose a cam optimized for that range.
• High RPM cams are better suited for racing or aggressive street riding.

Align your cam selection with how you use your motorcycle. Bigger isn’t always better when it comes to power.

2. Intake and Exhaust Valve Timing

Intake Opening and Closing

• Early intake opening enhances high RPM performance but can cause rough idling and lower fuel efficiency.
• Late intake closing sacrifices low-end power for gains at high RPMs.

Exhaust Opening and Closing

• Early exhaust opening improves scavenging but can reduce low-end torque.
• Late exhaust closing boosts low RPM performance and improves idle smoothness.

Fine-tuning these events is critical for achieving the right balance of low-end torque and high-end horsepower.

3. Lobe Separation Angle (LSA)

The Lobe Separation Angle is the degree of separation between the intake and exhaust lobes. This impacts overlap, which is when both valves are open.

• Narrow LSA (98°-103°):
• Better midrange power
• Fast engine response
• Rough idle
• Wide LSA (104°-108°):
• Broader power band
• Smoother idle
• Improved vacuum and emissions

Matching the LSA to your riding style ensures smooth power delivery and drivability.

4. Compression Ratio

Your choice of camshaft must align with your engine’s compression ratio. A mild cam operates well with a lower compression ratio, while an aggressive cam needs higher compression for proper combustion.

• Low compression ratio cams:
• Great for low RPMs, fuel efficiency, and reliability
• Avoid excessive heat stress
• High compression ratio cams:
• Designed for high RPM performance
• More heat and wear on the engine

Pairing the wrong cam with your compression ratio can lead to poor performance or even engine damage.

Popular Camshaft Specs and Their Implications

Duration

Duration is the time (measured in degrees of crankshaft rotation) that a valve remains open. It directly impacts power delivery:

• Short duration (<220°):
• Great for low-end torque
• Ideal for heavy bikes or touring motorcycles
• Medium duration (220°-235°):
• Balanced power curve for street and highway use
• Long duration (>235°):
• Best for higher RPMs and racing bikes

Lift

Lift refers to how far the valve opens. While high lift increases airflow and horsepower, it also adds stress to the valve train. For street motorcycles, lift values under 0.500” are typically sufficient.

• Low lift (<0.500”):
• Ideal for street bikes
• Stable and reliable with factory components
• High lift (>0.500”):
• Suitable for racing but requires upgraded heads and valve springs

Common Missteps to Avoid

1. Over-Camming
   Using an overly aggressive camshaft on a low-performance engine often backfires, decreasing low-end power and making the bike harder to ride.
2. Neglecting Tuned Combos
   Your camshaft works alongside other components like heads, exhaust pipes, and air filters. Ignoring this system can result in subpar performance.
3. Relying on Stock Heads
   Stock heads often restrict what high-performance cams can achieve. For Stage 2 upgrades, consider ported heads with stock-sized valves for optimal flow.
4. Overlapping Too Much
   Excess overlap can cause poor low-end idle and increased emissions. Choose overlap suitable to your application.

How to Match Your Cam to Your Riding Style

Here’s a quick guide to help you choose a camshaft based on how you ride:

Pairing Cams with Exhaust and Air Systems

Remember, a camshaft alone isn’t enough for your Stage 2 setup. Optimal performance comes from pairing the cam with:

• A high-performance exhaust to improve scavenging
• A high-flow air filter to ensure unrestricted airflow
• Proper tuning or fuel management systems to address air-fuel ratios

If your camshaft, exhaust, and intake systems aren’t aligned, you won’t experience the full benefits of your upgrade.

Final Thoughts and Expert Advice

Choosing the right camshaft for your motorcycle Stage 2 upgrade isn’t just about chasing horsepower. It’s about achieving a balance between torque, performance, and the kind of riding you enjoy. Whether you’re cruising at low RPMs or twisting the throttle wide open at high speeds, the right cam can elevate your motorcycle’s potential.

If you’re ready to improve your bike’s performance, explore our premium M8 cam kits designed for different riding styles. Need help selecting the right cam? Contact our motorcycle experts for tailored advice.

Take the next step in optimizing your motorcycle today!

FAQs About Motorcycle Cam Selection and Stage 2 Upgrades

1. What is a camshaft, and why is it important?

A camshaft controls the timing of the intake and exhaust valves in your motorcycle's engine. It plays a vital role in determining the engine's performance, affecting torque, horsepower, fuel efficiency, and throttle response.

2. What is a Stage 2 upgrade?

A Stage 2 upgrade typically includes enhancing your motorcycle's power by replacing the camshaft and improving components like the intake, exhaust, and tuning systems. This upgrade is designed to deliver better overall performance and responsiveness.

3. How do I choose the right camshaft for my motorcycle?

To choose the right camshaft, consider your riding style and RPM range. For touring or commuting, focus on cams designed for low-end torque. For racing or aggressive riding, prioritize high-performance cams optimized for mid-to-high RPMs.

4. What happens if I select the wrong camshaft?

Choosing the wrong camshaft can lead to reduced performance, rough idling, or increased wear on your engine. It’s crucial to match the camshaft specs to your riding style and engine setup.

5. What’s the difference between 'over-camming' and 'under-camming'?

• Over-camming means selecting a camshaft too aggressive for your engine, leading to poor low-end torque and rough performance.
• Under-camming involves a camshaft that’s too mild, limiting your engine’s ability to maximize high-end power.

6. Should I pair a cam upgrade with other modifications?

Yes. To maximize the benefits of a camshaft upgrade, pair it with a high-flow intake, performance exhaust, and proper engine tuning. These components work together to improve airflow and overall performance.

7. What is a lobe separation angle (LSA), and why does it matter?

The LSA is the angle between the intake and exhaust cam lobes. It influences power delivery, idle quality, and throttle response. Narrow LSAs are ideal for midrange power, while wide LSAs provide smoother idling and a broader power band.

8. How does a camshaft affect compression ratio?

The camshaft's valve timing directly impacts the engine's effective compression ratio. Mild cams work better with lower compression ratios, while aggressive cams require higher compression for optimal performance.

9. Can I install a high-lift cam without upgrading other components?

It depends on the lift's magnitude. High-lift cams often require upgraded valve springs and cylinder heads to prevent damage and ensure efficient performance.

10. How does camshaft duration influence performance?

Duration is the time the valves remain open.

• Short duration cams improve low-end torque.
• Medium duration cams provide a balanced power curve.
• Long duration cams enhance high-RPM performance but reduce low-end power.

11. What is camshaft overlap?

Overlap occurs when the intake and exhaust valves are open simultaneously. It’s crucial for scavenging exhaust gases and improving mid-to-high RPM performance but can hurt low-RPM idle quality.

12. Should I port my cylinder heads for a cam upgrade?

Porting cylinder heads can enhance airflow, making high-performance cams more effective. Stock heads often limit the potential benefits of aggressive camshaft upgrades.

13. What is the ideal cam for touring motorcycles?

For touring motorcycles, opt for a cam with:

• Short duration (under 220°)
• Conservative lift (<0.500”)
• Wide LSA for smooth idle and low-end torque.

14. How do I know if my cam needs tuning adjustments?

Common signs include rough idling, poor throttle response, or noticeable performance drop-offs in specific RPM ranges. Proper tuning ensures the camshaft delivers its intended benefits.

15. Can cams improve fuel economy?

Cams designed for low-end torque can improve fuel economy by optimizing combustion efficiency. However, cams focused on high-end power may increase fuel consumption.

16. What’s the biggest advantage of a Stage 2 cam upgrade?

A Stage 2 cam upgrade significantly boosts power and torque, enhancing acceleration and overall performance, especially in low to mid RPM ranges.

17. How often do camshafts need to be replaced?

Camshafts are durable components, but their lifespan can be reduced by aggressive use, improper installation, or lack of maintenance. Regular inspections can help identify wear and tear.

18. Is a camshaft upgrade worth it?

Absolutely! A camshaft upgrade is one of the best ways to dramatically improve your bike’s performance, especially when combined with other Stage 2 components.

19. Do I need professional help to install a camshaft?

While experienced mechanics can install a camshaft, professional installation is recommended to ensure correct alignment, proper tuning, and maximum performance.

20. Where can I find reliable cam kits for my motorcycle?

You can explore our premium M8 cam kits designed for various riding styles. Visit our store or contact our team for recommendations tailored to your needs.