- 1). Position a motorcycle lift under the engine and raise the bike off the ground. Loosen the clamps at the top of each fork just under the tension nuts with a ratchet set. Loosen the tension nuts with an Allen wrench.
- 2). Place a drain pan under the nut at the bottom of the fork. Turn the nut counterclockwise to release the air or drain the oil. Pull the two forks from the clamp.
- 3). Pry the plastic fork seal off the fork with a flat head screwdriver. Slide the old seal off of the fork and slide a new seal onto the fork. Push down on the new seal until it snaps into place.
- 4). Place the forks back into the clamps. Tighten the clamps and the tension nuts to the torque specifications.
- 5). Fill the forks with air or oil according to that specific YZ 250. Lower the bike to the ground.
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