Telescopic fork checklist for optimization

Chassis problems can have a variety of causes – initially

• the tires must be checked for correct air pressure and tread depth, a different tread can sometimes work wonders
• the wheels must run smoothly and free of play, and must not have any lateral or vertical runout
• the rear swing arm should not allow any play to be felt in the bearing or on the reversing levers
• the shock absorber must be tight and the spring intact
• the steering head bearing must run smoothly and free of play, the Simmerrings must be tight, the clamping screw on the front axle and fork bridge must be tightened
• the screw connections of the chassis (front, rear axle, engine, frame) must be tightened as specified
• the chain must be OK, properly tensioned and lubricated

Fork cuts through

• Possible cause: Preload too low Measure: Increase preload (insert bushing or washers)

• Possible cause: Air cushion too big Measure: Increase oil level

• Possible cause: Insufficient compression stage damping Measure: Set damping higher (if available)

• Possible cause: Additional air pressure too low Measure: Increase air pressure (if possible)

• Possible cause: too thin fork oil Measure: increase viscosity

• Possible cause: too soft or linear springs Measure: install progressively harder WIRTH springs

Fork does not respond properly, is uncomfortable, handlebar knocks (kickback)

• Possible cause: Pre-tension too high Measure: Lower the pre-tension (e.g. remove or shorten spacer bushing)

• Possible cause: Air cushion too small Measure: Carefully reduce the oil level

• Possible cause: high compression damping Measure: decrease damping (if available)

• Possible cause: Additional air pressure too high Measure: Reduce air pressure (if possible)

• Possible cause: too thick fork oil Measure: reduce viscosity

• Possible cause: springs that are too hard or linear Measure: install progressively softer WIRTH springs