Replacing the Starter Ring Gear on the Motorcycle Dyno Dynojet Research, Inc. 200 Arden Dr.
Starter Ring Gear Replacement This manual explains the replacement procedure for the starter ring gear on a motorcycle dynamometer. Removing the Old Ring Gear Step 1 If your dyno is equipped with a brake, it will be necessary to remove it before proceeding. If your dyno is not equipped with a brake, please proceed to step 2. Remove the caliper assembly by removing the (4) 3/8 bolts that hold it to the frame. Remove the Banjo Bolt You will also need to remove the brake line from the caliper.
Step 2 Remove the (12), (8) if you had to perform step 1, 3/8” hex bolts on the rear section of the frame. Remove the “C” channel section of the frame. Step 3 Measure and take note of the drum orientation inside the frame. This is crucial, as the dyno drum needs to be replaced in the exact same location as it was before replacing the starter ring. Take measurements from the face of the drum to the edge of the frame on both sides. Take this Measurement on both sides of the drum.
Step 5 Use a forklift and nylon straps capable of supporting 1000 lbs and lift the drum and frame a few inches. Set a piece of 1/4” plywood between the frame rails under the drum. It should be long enough so when you remove the drum it remains on the plywood. Lower the drum and frame down so only the drum sits on the plywood. Step 6 Remove the (8) 5/8” nuts and lock washers from the bearings on each side of the dyno. Remove the bearings and set them aside.
Step 2 Heat the new starter ring until it “grows” enough to fit over the drum. Be sure the ring is seated at an equal distance around the perimeter of the drum, and hold it in place until it cools. Step 3 You may want to prime / paint the new ring gear and the area on the drum surface where you were working. Step 4 Roll the drum assembly back into the frame, and be sure the bearing bolts are still in place through the holes on the inside of the frame.
Lift the drum assembly as you did in Step 5 of Section 1, and remove the plywood. Set the drum / frame down, and then tighten the bearing bolt nuts on both sides to 150 lbs-ft. Step 5 Replace the bearing lock collars on both sides of the dyno. Be sure the drum is located EXACTLY in the same location as when you removed it (reference the measurements you recorded earlier). Set the lock collars (refer to sticker above bearing), and then tighten down the set screws to 28 lbs-ft.
Dial indicator Step 9 Attach the caliper assembly with (4) 3/8” hex bolts and torque them to 42lbs-ft.. Step 10 Adjust the brake as necessary to allow the rotor to spin free of contact. Loosen the jam nut, and use the adjustment nut to move the brake pads in or out. Step 11 Attach the brake line back to the caliper. You will most likely need to add fluid (DOT 5) and bleed the system of air. Step 12 Make a final inspection and be sure that all fasteners are tight and that the drum rotates freely.
