How to Tighten the Chain on a Yamaha Raptor
- 1). Lift the ATV's rear wheels off of the ground, using a jack placed below the engine. Support the ATV's frame with jack stands.
- 2). Grasp the chain's upper strand between the front and rear sprockets. Measure the chain's slack, using a ruler or tape measure, by pushing down firmly on the chain, then lifting the chain as far as it will move. Ideally, the chain must have a range of motion between 1.18 inches to 1.77 inches.
- 3). Spin the rear wheels until the hub nuts on the right side of the rear swingarm are visible through the holes cut into the rear brake disc. Loosen the hub nuts, using a socket wrench an a 14 mm socket.
- 4). Loosen the chain adjuster lock nuts on both sides of the rear swingarm, facing the engine, using a 12 mm crescent wrench.
- 5). Turn both chain adjuster bolts, using a socket wrench and a 12 mm socket clockwise to loosen the chain, or counterclockwise to tighten the chain. Turn the bolts in even amounts to keep the rear wheels aligned. Check the chain slack periodically, as described above, and make adjustments until the chain slack is between 1.18 inches to 1.77 inches.
- 6). Check the rear wheel alignment, using the alignment notches cut into both sides of the swingarm and both rear axle hubs. Adjust the tightest side of the rear axle, using the chain adjuster bolts, until both rear axle hub notches are aligned with the corresponding swingarm notch.
- 7). Check the chain slack again, as described above. Tighten the chain adjuster lock nuts against the swingarm, using a 12 mm crescent wrench, if the chain slack is between 1.18 inches to 1.77 inches. Adjust the chain, as needed, if the chain slack is not within the specified range.
- 8). Tighten the rear hub nuts to 65 foot-pounds, using a torque wrench and a 14 mm socket.
- 9). Remove the jack stand and lower the ATV's rear wheel to the ground.
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