Motorcycle Final Drives
Final Drive Basics
Motorcycle final drives are designed to transfer power form the motorcycle's transmission to the rear wheel. This can be accomplished by either a belt drive or chain drive. For most riders, or custom chopper builds, either type will perform adequately, but there are some inherent differences. Shaft drives are also available, but will not be included in this article.
Final Chain Drives
The most common motorcycle final drive is the chain drive, and it is still standard on many manufactured bikes. Much like the chain primary drive, sprockets are used to transfer rotational movement from the transmission to the rear wheel. Chain drives are comparatively narrower than belt drives, and therefore lend themselves to fat tire custom choppers where clearance and overall width is an issue.
Chain drives may be the superior choice when considering high horsepower applications. Chains are not as susceptible to slipping under high torque situations, and ganged chains, chains that are locked together side-by-side, can be used for drag racing or extreme horsepower conditions. Final drive ratios can be easily changes by swapping sprockets. Chain drives should be inspected regularly, and must be lubricated for proper operation
Final Belt Drives
Motorcycle final belt drives are readily available on off-the-shelf bikes and as options for custom motorcycle and custom chopper options. Instead of sprockets, belt drives use pulleys to transfer the power from the transmission to the rear wheel. For most riders belt drives will provide the necessary performance characteristic, without the messy lubrication of chain drives.
It should be noted that in high horsepower applications, such as drag racing, belt drives may not be the best choice. Belts are susceptible to "skipping" and breakage if the belt drive is not properly matched to the conditions for which it is being used. Typically wider than chain drives, final belt drives may may require additional spacers or offsets for optimal clearances in fat tire customs. Drive belts should be inspected regularly for cracks, tears and wear.
Final Drive Comparison
The chart below will give a quick comparison, the ups and downs, between chain drives and belt drives.