The YFZ350 Banshee is one of Yamaha's most notorious sport-biased all-terrain vehicles ever produced. Initially introduced in 1986, the Banshee would continue to be sold in the US with relatively few changes until 2006. The Banshee was powered by a variation of Yamaha's two-stroke RZ350-streetbike engine that was renowned for its astonishing power output versus its engine displacement. The Banshee relied on a solid axle held in a carrier tube on the rear swingarm. A pair or bearings ensured that the axle could spin freely, but were easily damaged by rough terrain. Damaged bearings can allow the rear axle to move around, reducing stability and eventually wearing away at the axle material.
Things You'll Need
- Metric socket set
- Breaker bar
- Hook-type spanner wrench
- Open-end wrench set
- Parts-cleaning solvent
- Oil seals
- Ring nuts
- Torque wrench
- Cotter pins
Park your Banshee on a flat, level surface and set the parking brake. Loosen the rear wheel lug nuts, using a socket and a breaker bar. Remove the cotter pins from the the hub nuts at the center of both rear wheels, using pliers. Loosen the hub nuts, but do not remove them at this time.
Release the parking brake and lift the rear wheels off of the ground, using a jack placed under the ATV's engine and frame. Unscrew the rear wheel lug nuts, using a ratchet, then pull the wheels off of the rear wheel hubs. Unscrew the hub nuts, then pull both rear wheel hubs off of the rear axle.
Have an assistant push down on the rear brake pedal to lock the rear axle in place. Unscrew the pair of ring nuts securing the rear brake rotor holder and sprocket carrier to the left side of the rear axle, using a hook-type spanner wrench. Release the rear brake pedal.
Loosen the bolts along the top and bottom of the rear axle carrier, the tube that the rear axle spins in on the rear swingarm, using a ratchet and a socket. Loosen the chain adjuster lock nuts, located under the both sides of the rear axle carrier, using an open-end wrench. Turn the adjuster bolts counterclockwise with the wrench until you the drive chain is loose enough to be lifted completely off of the sprocket. Do not remove the chain yet.
Unbolt the rear brake caliper from its swingarm-mounted bracket, using a socket and a ratchet. Lift the caliper off of the rear brake rotor, then suspend the caliper from the Banshee's frame, using a bungee cord.
Slide the rear brake rotor and its holder off of the left side of the rear axle. Lift the chain off of the sprocket, then slide the sprocket carrier off of the left side of the rear axle. Pull the axle out from the right side of the swingarm.
Unscrew the upper and lower rear axle carrier bolts, using a ratchet and a socket. Pull the chain adjusters away from the bottom of the axle carrier, then pull the carrier away from the swingarm.
Pry out the oil seals from both sides of the rear axle carrier, using the tip of a flat-head screwdriver. Insert a long drift through the bearing on one end of the carrier until it is resting against the back of the bearing on the opposite end of the carrier. Tap the bearing out of the carrier, using the drift and a mallet. Pull out the internal spacer, then repeat to remove the remaining bearing.
Clean the bearing mating surfaces on both ends of the rear axle carrier with a parts-cleaning solvent, then wipe dry.
Turn the rear axle carrier onto one side, then lay a new bearing into the end of the carrier. Drive the bearing into place, using a socket with a diameter that matches the bearing's diameter and a mallet. There should be enough room between the edge of the axle carrier and the bearing to seat the oil seal. Drive the oil seal into place over the bearing, using the same socket. Flip the rear axle carrier over and insert the internal spacer. Drive the remaining bearing and oil seal into place.
Re-install the rear axle carrier and chain adjusters onto the rear swingarm. Loosely tighten the upper and lower carrier bolts. Slide the rear axle through the right side of the carrier until it stops. Slide the sprocket carrier and rear brake rotor holder onto the left side of the rear axle. Pull the drive chain over the sprocket.
Screw two new ring nuts into place at the left side of the rear axle. Tighten the inner ring nut -- the nut closest to the center of the axle -- to 94 foot-pounds, using a torque wrench. Tighten the outer ring nut to 140 foot-pounds, then tighten the inner ring nut against the outer ring nut to 170 foot-pounds.
Slide the rear brake caliper over the brake rotor and into its mounting bracket. Tighten the caliper bolts to 17 foot-pounds. Pump the rear brake pedal until it feels firm, then have an assistant hold the pedal in place.
Slide the rear wheel hubs onto both ends of the axle and screw the hub nuts into place. Tighten the hub nuts to 85 foot-pounds, then loosen the nut slightly to align the nut's notches with the hole drilled into the end of the axle. Push a new cotter pin through each hole, then bend the pin legs around the nuts with pliers. Have your assistant release the rear brake pedal.
Mount the rear wheels onto the hubs and screw the lug nuts into place hand-tight. Lower the rear wheels to the ground and tighten the lug nuts to 32 foot-pounds in a star-shaped pattern.
Turn the chain adjuster bolts clockwise an even amount of turns until the drive chain has 0.6-inch of slack. Tighten the adjust lock nuts against the adjusters. Tighten the upper axle carrier bolts to 85 foot-pounds and the lower carrier bolts to 43 foot-pounds.
Tips & Warnings
- Do not tighten the drive chain while the ATV is lifted off of the ground. Doing so will result in an over-tightened chain when the weight of the ATV is placed on the rear wheels. This can cause the chain to break when the ATV hits the slightest of bumps.
- Yamaha YFZ350 Service Manual; Yamaha Motor Corp.