| Classic CanAm |
MX-1 Restoration Project |
Section 3: The Chassis |
Steering Head: The original adjustable steering head cones and needle bearings were used for land fill. We replaced them with tapered bearings and races from a 1979 Qualifier. This fixes the steering head angle at 28 degrees. The original setting was 31 degrees and the bikes had a tendency to plow in corners. If you make this modification on a 125, the swingarm needs to be lengenthed or they get twichy at high speed because of the short wheelbase. Swingarm The swingarm is from a Q1 250. The reason for doing this was because the 250 swingarms are 1.5" longer than the stock 125. Since the steering head angle on this bike was fixed at 28 degrees, we wanted to compensate for any instability problems at high speed. The rubber pivot bushings were replaced with "Nylotron" bushings from a late model Qualifier. The old style rubber bushings flex, but the nylon bushings ride solid on a steel sleeve. It's a much better setup. But they require more maintance. You have to keep them clean and greased. Shocks: Suspenders are Progressive Suspension gas with 65 lb springs. They are 13" units which yield exactly 4.00" of travel with the Q1 swingarm. If you use a 250 TNT or MX1 swingarm you will need to run 12.5" shocks to keep your suspension legal for AHRMA competition. In hindsight, we would have chosen the TNT swingarm and 12.5" shocks to keep both of our race bikes the same. But this setup works fine. Forks: Forks are stock 6.5" travel Betors. Heavy duty springs replaced the old units. For our 200 lb rider, we use 220cc of 20w fork oil in each leg. Other than new seals, no other modifications were used. Wheels: The wheels are from an MX-2 125. The aluminum rims save a great deal of weight and are much stronger than the steel wheels. This setup is legal for AHRMA competition. Airbox: The original fiberglass airbox is heavy, and doesn't provide a good seal between the filter and box. It was replaced with a lightweight plastic TNT airbox, inner fender, and air filter. Weight savings is around 4 lbs. We originally used an NOS Twin Air filter but it disentigrated during the first ride. This was replaced with a brand new (not NOS) UniFilter 2 stage unit. The UniFilter also seals much better. |
