Chain and Sprocket Help

• Changing your gearing
• Standard gearing for most bikes
• Determining the pitch of a chain

The basics

Your bike will have a front and rear sprocket and a chain that links them to transfer the drive from the engine to the rear wheel. The difference between the number of teeth on the sprockets provides gearing in addition to that provided by the gearbox.

Changing your gearing

By changing your sprockets from the standard configuration you can alter the performance of your bike:

• Improved acceleration

  Increasing the number of teeth at the rear will make your bike accelerate faster but require more engine revs for a given speed compared to the standard configuration. Top speed will be reduced.

• Improved economy

  Reducing the number of teeth at the rear will make your bike accelerate slower and require less engine revs for a given speed compared to the standard configuration. Top speed will be increased.

The chain and both sprockets must all run the same pitch and be of suitable quality for the power of the bike.

Standard gearing for most bikes

If you aren't sure which gearing is present on your bike, please take a look at our Renthal chain and sprocket fitment guide (for bikes up to 2007). From this you will be able to identify the pitch you require, the length of the standard chain (measured in number of links) and the number of teeth present on standard fitment sprockets.

Some bikes (e.g. Yamaha YZF-R6) are manufactured using a chain pitch that's not generally available from aftermarket manufacturers. To overcome this, the aftermarket manufacturers typically offer 'conversion' kits which change the front and rear sprocket to mate with a chain of a slightly different pitch.

Determining the pitch of a chain

The pitch of a chain is determined by measuring the distance (in inches) between the centres of 3 consecutive rivets (shown as distance 'D' on the image below) and dividing by 2. For example, a 530 chain (5/8") will have a distance 'D' of 1.25 inches.

Motorcycle Chain Dimensions
Chain No.	Pitch	Roller Diameter	Roller Width	Sprocket thickness
420	1/2"	5/16"	1/4"	0.227"
425	1/2"	5/16"	5/16"	0.284"
428	1/2"	0.335"	5/16"	0.284"
520	5/8"	0.400"	1/4"	0.227"
525	5/8"	0.400"	5/16"	0.284"
530	5/8"	0.400"	3/8"	0.343"
630	3/4"	15/32"	3/8"	0.343"

For everything there is to know about chains please visit The Complete Guide to Chain website, by Tsubakimoto Chain Co.