Step 1: Install the Bearing Cassettes
- Slide the bearing cassettes into the chassis hangers. Ensure the pinch bolt screw faces toward the rear of the kart and the set screw section of the bearings faces inward on either side of the frame.
- 1.1: For a baseline setting, install the cassettes in the middle ride height position. Use the middle and lower section holes for the bolts as a starting point.
- 1.2: When installing the hex bolts to secure the cassette:
- First, turn each bolt in by hand a significant amount to avoid cross-threading before using a socket or wrench.
- Tighten all cassette bolts fully with your wrench once they’re started.
- 1.3: Note: If the frame is new, the powder coat may make the bolt holes tight, causing initial difficulty. Be patient; the bolts will screw in properly with care.
- 1.4: Note: The how-to video guide shows a black plastic disc protector on the brake side. This is no longer included in the kit, so disregard it.
Mount Brake Caliper Bracket to Cassette
Step 2: Attach the Brake Caliper Bracket
- Take the brake caliper mount and provided hardware to secure it to the bearing cassette. Use the spacers between the caliper bracket and cassette.
- 2.1: Position the M8 hex bolt with the head against the caliper bracket side, going inward toward the cassette. Avoid installing it with the hex head on the outside of the cassette, relying only on the M8 nut to hold the bracket.
- 2.2: Tighten the caliper bracket support bolts using a 13mm wrench. Ensure they are firmly tightened to prevent movement during driving.
- 2.3: After tightening, some bolt threads should protrude from the cassette. Install the M8 nylock nut for added security, holding the hex bolt head with a wrench while tightening the nut to prevent loosening.
Mount Brake Caliper to Bracket
Step 3: Secure the Brake Caliper to the Bracket
- Remove the flange nuts from the upper and lower bolts of the caliper to free the bolts.
- 3.1: Insert an M10 screw through the top and bottom holes of the caliper bracket.
- 3.2: Slide the caliper halves back onto the bolts and secure them with M10 flange nuts on both screws.
- 3.3: Fully tighten the caliper to the bracket using an M8 Allen key and a 17mm wrench.
Set the Axle into the Bearings
Step 4: Prepare and Install the Axle
- Loosen the cassette pinch bolt to allow movement during axle installation. Note that even loosened, new bearings and cassettes may still feel tight.
- 4.1: Remove all bearing set screws to avoid scarring the axle during installation, which could cause future issues. The axle should slide through with minimal resistance.
- 4.2: Spray and wipe the axle with a lubricant (e.g., WD-40) to ease sliding into the bearings.
- 4.3: Orient the axle correctly before insertion:
- Check the logo etchings in the middle; they should read normally when standing behind the kart looking forward.
- Alternatively, note the keyway slots: 3 on the motor side, 2 on the brake side.
- 4.4: Insert the axle starting on the motor side, sliding it through until it reaches the brake side bearing opening.
- 4.5: Align the bearings for smooth axle installation:
- Let the axle rest and visually check its position relative to the brake side bearing’s edge. If it rests significantly lower, apply downward pressure on the motor side to raise it, then recheck alignment. Aim for equal distances top-to-bottom.
- Repeat the process side-to-side to ensure even alignment.
- Pull the axle back out from the motor side, insert it from the brake side until it reaches the motor side bearing, and repeat the alignment checks.
- Retighten the cassette pinch bolts to secure the alignment.
- 4.6: With both bearings aligned, push the axle through fully to proceed with component installation.
Install Axle Keyways, Brake Hub Assembly, Sprocket, and Wheel Hubs
Step 5: Assemble Components onto the Axle
- Slide the axle to the right (from behind the kart) until it clears the brake side bearing.
- 5.1: Install the brake hub/disc assembly:
- Loosen the brake hub pinch bolts and slide the hub onto the axle, ensuring it’s square for easy installation. The pinch bolt section should face right (toward the motor side).
- Slide the axle back into the brake side bearing for support after the hub is on.
- Insert an axle keyway into the holes where the brake hub will lock into place. Use a metal hammer if needed to tap it in due to tight tolerances.
- Push the axle further to position the hub, measuring from the outer face of the bearing cassette to the axle end. Match this distance on the opposite side (±1mm tolerance).
Secure the Axle into Position
Step 6: Lock the Axle in Place
- Confirm the axle is aligned from Step 5 measurements.
- 6.1: Install the three set screws per bearing:
- Apply a dab of blue Loctite (blue only) to each set screw to prevent loosening.
- Tighten each screw with a 4mm Allen wrench until it touches the axle, then add a ¼–½ turn to slightly dig into the axle. Repeat for all set screws on both bearings.
- Caution: Over-tightening can dent the axle over time, distorting its shape and complicating removal.
Install Sprocket Hub and Rear Wheel Hubs
Step 7: Mount the Sprocket Hub and Wheel Hubs
- Insert a keyway into the slot just outside the right-side bearing for the sprocket hub.
- 7.1: Loosen the hub pinch bolts, slide the sprocket hub onto the axle, and snug the bolts to prevent movement (full tightening comes later with drivetrain alignment).
- 7.2: Place the remaining two keyways into the outermost holes on each axle end, tapping them in with a metal hammer if needed.
- 7.3: Slide on the rear wheel hubs:
- Tighten the pinch bolts with a 6mm Allen wrench until they stop, then add ½–1½ turns for a secure fit.
Install Motor Stop Bolt
Step 8: Add the Motor Stop Bolt
- Screw the motor stop bolt into the spud located inside the bearing cassette hanger.
Final Inspection
Step 9: Verify Installation
- Rotate the axle to ensure smooth movement.
- 9.1: Note: New bearings with packing grease may feel stiff initially. Spray Tri-Flow lubricant into the bearings to free them up, especially between track sessions.
- Check all components for tightness and proper alignment.
