7. Front forks: aligning the damping components
- Due to their long travel and relatively complex construction, these forks can be noisy in operation or, especially after they have been disturbed, they can become stift in operation. While the standard procedure described in Section 5 - Front forks: reassembly and Section 6 - Front forks: refitting of this Chapter is sufficient in most cases, to remedy this. On occasion a stift or noisy fork can be cured only by the more elaborate procedure described below. Note that the procedure starts with the premise that the stanchions are in place on the machine, with the damper rods fitted, and that the lower legs are attached loosely by the damper rod Allen screws; the mudguard, front wheel and fork brace (if fitted) must be removed.
- Push each lower leg sharply upwards until it is heard to make contact, then rotate it two or three times around the stanchion to centre the damper rods before tightening the damper rod Allen screw to the specified torque setting (where given); use the spring or a wooden dowel to prevent the damper rod from rotating. Check that the lower leg still slides smoothly and easily and rotates without stiffness; if necessary slacken the Allen screw and repeat the procedure until results are satisfactory.
- If a fork brace is fitted, install it but tighten the bolts only lightly then refit the wheel spindle and clamp it on one side only. Push both lower legs upwards simultaneously until contact is heard again then tighten the fork brace mounting bolts evenly and in a diagonal sequence to the specified torque setting; tighten also the second pair of spindle clamp bolts to the specified torque setting.
- Pump the lower leg assembly up and down several times to check for any signs of stiffness or distortion, then check that the wheel spindle can be easily removed and refitted. If any stiffness or difficulty is found, check the fork components for distortion.
- Refit the oil drain plugs, the front mudguard, the front wheel and the brake components then fill each leg with the specified quantity and type of fork oil and refit the fork springs and spacers.
- Raise the front wheel from the ground and support the machine with a wooden box or similar under the crankcase so that the forks are fully extended. Refit the top plugs and oil filler plugs, then lower the machine to the ground and check the fork action.
- Note that some stiffness will be inevitable in a freshly-rebuilt fork and a running-in period of 600 miles (1000 km) will probably prove necessary before the fork operates with absolute smoothness.