1. What is Crank To Wheel Horsepower?

Wheel horsepower (WHP) is the amount of power that actually reaches the wheels after accounting for drivetrain losses. It's typically about 15% less than crank horsepower (CHP) due to mechanical losses in the transmission, chain/belt drive, and other components.

2. How Does the Calculator Work?

The calculator uses the standard conversion formula:

Where:

• \( WHP \) — Wheel horsepower (power at the wheels)
• \( CHP \) — Crank horsepower (engine output)
• \( 0.85 \) — Standard drivetrain loss factor (15% loss)

Explanation: This formula provides a rough estimate of wheel horsepower based on the manufacturer's crank horsepower rating.

3. Importance of WHP Calculation

Details: Wheel horsepower is what actually propels your motorcycle forward. Knowing your WHP helps in performance tuning, comparing actual performance between bikes, and understanding real-world power delivery.

4. Using the Calculator

Tips: Enter your motorcycle's crank horsepower (as specified by the manufacturer) to estimate the power reaching the rear wheel. The 15% loss factor is typical but can vary slightly between different drivetrain configurations.

5. Frequently Asked Questions (FAQ)

Q1: Is the 15% loss factor accurate for all motorcycles?
A: It's a general estimate. Actual drivetrain losses can range from 10-20% depending on the type of transmission (chain, belt, or shaft drive) and other factors.

Q2: Why is WHP lower than CHP?
A: Power is lost through friction in the transmission, chain/belt drive, and other mechanical components between the engine and wheels.

Q3: How can I measure actual WHP?
A: The most accurate way is to use a dynamometer (dyno) which measures power directly at the wheel.

Q4: Does WHP vary with different modifications?
A: Yes, changes to gearing, tire size, or drivetrain components can affect the percentage of power that reaches the wheels.

Q5: Is this calculator suitable for all types of motorcycles?
A: It works for most chain- and belt-driven motorcycles. Shaft-driven bikes typically have slightly higher drivetrain losses (around 20-25%).