How to Tighten a Harley Belt Drive

Harley-Davidson has been making motorcycles continuously since 1903. For many years Harley-Davidson motorcycles were powered by a chain drive, but Harley switched from a chain drive to a flexible toothed rubber belt in 1980. The belt is quieter than a chain and does not require messy lubricants, but, like a chain, the belt will stretch with wear and will need to be adjusted. The proper tension of the belt drive is important. If the belt is too loose, it can whip around and eventually break. If a belt is too tight, it can put excessive strain on the transmission and wheel bearings. The belt can be easily adjusted with regular tools in about one hour.

Difficulty:

Moderate

Instructions

Things You'll Need

• Adjustable wrench
• Ruler
• Torque wrench

1. • 1

     Locate both rear axle nuts on the rear suspension swing arm on each side of the wheel hub. Slacken off but do not remove the nuts in a counterclockwise direction with an adjustable wrench.

   • 2

     Locate the axle adjusting nuts at the rear of the swing arm on each side of the bike. Use an adjustable wrench and turn each nut an equal number of turns in a clockwise direction to tighten the belt.

   • 3

     Check belt deflection when the bike is cold (it has not been ridden in several hours) with a rider sitting on the seat and the side stand up. Depress the belt at the middle point between the front and rear belt sprockets with your thumb and measure the amount of deflection with a ruler. Ensure belt deflection is between 5/16 inch and 3/8 inch. Make final adjustments on the axle adjusting nuts with the rider sitting on the bike until these measurements are obtained.

   • 4

     Tighten the rear axle nuts in a clockwise direction with an adjustable wrench.

   • 5

     Torque the rear axle nuts to between 60 and 65 foot-pounds of torque with a torque wrench.

Tips & Warnings

• When making belt adjustments, always turn the axle adjusting nuts a like number of turns on each side to retain rear axle alignment.

• To make a simpler job out of checking belt tension, use a belt tension gauge, which you can find at your Harley-Davidson dealer.

• Periodically check your drive belt for damage and excessive deterioration. Replace a drive belt with any defects.