How To Build the GPS Drift Quad

How to Build the GPS Drift Quad Roller Kit

Welcome to the official step-by-step build guide for the GPS Drift Quad Roller Kit! This guide covers the assembly of the rolling chassis. Whether you went with the beefy 15" Street Tire package or the aggressive Racing Wheel setup, this guide will get your frame sitting on all four wheels.

Builder's Pro-Tip: The "Dry Mockup"
We highly recommend doing a complete "dry mockup" assembly before sending your frame off to paint or powder coat. It is always best to ensure everything fits perfectly, drill your seat/tank holes, and test your riding position before applying a $300 custom finish that could get scratched or require grinding!

🛠️ Tools Required

You won't need a massive mechanic's chest to build this quad. Gather these basic hand tools before you begin:

• Metric Allen Key Set: (Specifically 3mm, 4mm, 5mm, 6mm, and 8mm)
• Standard & Metric Sockets: 8mm, 10mm, 12mm, 13mm, 7/16", 1/2", 9/16", 3/4", and 15/16" (if you don't have a 15/16" socket, large pliers or a crescent wrench will work for the spindle nuts).
• Standard & Metric Wrenches: 10mm, 12mm, 13mm, 9/16", and 3/4"
• Large Crescent Wrench: Needs to open to at least 1-1/8" for the rear axle nuts
• Ratchet & Extensions
• Phillips Head Screwdriver
• Wire Snips / Cutters
• Rubber Mallet (or a standard hammer, used carefully)
• Tape Measure (Crucial for dialing in your alignment)
• Sharpie or Marker
• Power Drill with a 1/4" drill bit (for the seat) and a 1/2" bit (for the gas tank petcock)
• Optional but helpful: Impact wrench (use on the lowest setting to avoid over-torquing)

Phase 1: Frame Prep & Front Axle

1. Mount the Front Axle: Slide the detachable front axle into the main frame from the side. The modular design makes replacement easy if you ever hit a curb!
2. Secure the Axle: Line up the 4 bolt holes. Insert the bolts with a washer on the top and a washer on the bottom, followed by the nut.
3. Tighten: Use your 3/4" wrenches/sockets to tighten the bolts evenly. Alternate side-to-side so the axle seats perfectly flush against the frame.

Phase 2: Front End & Steering

1. Install the Spindles: Orientation is critical here! Slide the spindles into the brackets so the steering arms are positioned on the bottom and are pointing towards the back of the quad.
2. Add the Springs: Insert the suspension spring between the spindle and the upper bracket. (Note: For this dry mockup, skip the grease. During your final build after paint, apply grease inside the spindle, on the bolt, and on top of the spring for buttery smooth steering.)
3. Adjust Your Steering Ratio: The steering shaft features multiple mounting holes to dictate your steering speed.
   • Mounting higher up: Fast, aggressive steering (perfect for drifting and quick recovery).
   • Mounting lower down: Slower, relaxed steering (perfect for high-speed neighborhood cruising).
4. Mount the Tie Rods: Place a lock washer between the tie rod end and the mounting point to allow the tie rod to articulate properly. Secure them with a 9/16" wrench, but leave the adjustment nuts loose for now.
5. Mount the Front Wheels: Slide your front wheel spacers onto the spindles, followed by the wheels.
6. Tighten Spindle Nuts: These bearings have built-in snap rings, so there are no crush sleeves. Using a 15/16" socket (or pliers), tighten the nut until you feel a little drag on the wheel, then back it off slightly so the wheel spins freely.

Phase 3: Handlebars & Alignment

1. Mount the Handlebar Risers: Use your 6mm and 8mm Allen keys. The riser holes are drilled slightly off-center. Mount them with the offset hole facing the back to push your handlebars forward for an aggressive stance.
2. Install the Handlebars: Drop the 7/8" bars into the risers. Use the textured grooves on the bars to center them perfectly. Keep the GPS logo pointing backward. Snug the top bolts, then tighten the bottom bolts securely (they feature lock washers).
3. Align the Front End: Point your handlebars dead straight. Take your tape measure and measure from the center of the left front tire to the center of the right front tire (do this at the front edge of the tires, and then the back edge of the tires).
4. Adjust Toe: Twist the tie rods until your front and rear measurements match exactly (around 34 inches depending on your tires). This is "zero toe" and a great starting point.
5. Lock the Tie Rods: When tightening the 9/16" jam nuts, manually twist the tie rod ends in the same direction before locking them down. If they are twisted in opposite directions, the steering will bind when you turn!

Phase 4: Foot Pans & Chain Roller

1. Mount the Foot Pans: Slide them onto the frame standoffs. Use a washer on top and the serrated nut on the bottom (10mm top / 12mm or 13mm bottom). The foot pans are designed to have a slight amount of "float" to them, so just hold the bottom nut by hand until it bites and tighten.
2. Install the Chain Roller: Use a 10mm and 13mm tool. The chain roller is designed to float side-to-side on its bolt to ensure perfect alignment with your engine later. Tighten the bolt just until the threads pass through the nylon lock nut, ensuring the roller can still easily slide side-to-side.

Phase 5: The Rear Axle Assembly

Take your time here! Setting up a live axle requires doing things in a specific order so you don't have to take it all apart later.

1. Prep the Brake Bracket: Mount the brake caliper bracket to the frame using the two 5/16" bolts. Washer and bolt head on top, two flanged serrated nuts on the bottom.
2. Prep the Sprocket Carrier: Insert the six 1/4-28 bolts through the carrier to act as studs. Slide the split sprocket over the studs. Ensure the split lines up perfectly, compress it together by hand, and run the flanged nuts down until they are snug but the sprocket can still shift slightly. Align it perfectly, then tighten it down.
3. Hang the Bearings: Mount the flangettes and bearings to the rear frame plates using the 13mm bolts and nuts. The 3 holes form an equal triangle, so orientation doesn't matter. Leave these slightly loose to make sliding the axle easier.
4. Build the Axle Stack: Slowly feed the 1" axle through one bearing, then slide your components onto the axle in this exact order before passing it through the opposite bearing:
   • Bearing lock collar
   • Axle slide stop lock collar
   • Brake disc lock collar
   • Brake disc
   • Brake disc lock collar
   • Sprocket lock collar
   • Sprocket Carrier (with sprocket)
   • Sprocket lock collar
   • Axle slide stop lock collar
   • Bearing lock collar
5. Center the Axle: Measure from the frame bracket to the end of the axle on both sides. Shift the axle until it is perfectly centered (roughly 12+ inches sticking out on each side).
6. Lock the Bearings: Once centered, fully tighten the 3 bolts on your bearing flangettes.
7. Set the Hardware: Roughly align your brake disc with the caliper bracket, and your sprocket with the chain roller. Slide your 1/4" x 1-1/4" keys into the slots. Use a 5mm Allen to tighten the lock collars around them (leave the sprocket slightly loose until your engine is mounted later).
8. Mount the Brake Disc: Thread the brake disc to the caliper bracket using the two 8mm bolts with lock washers (13mm socket).

Phase 6: Rear Wheels & Hubs

1. Slide on the Rear Wheels: Slide a lock collar onto the axle end, followed by your rear wheel.
2. Set Your Wheel Width: For the best grip, set your rear wheels slightly narrower than your front end. Measure from the frame to the inside of the tire. Ensure both sides are identical (roughly 9-3/8" off the frame, aiming for a 33.5" center-to-center rear width).
3. Lock the Wheels: Once you have the exact width, push the lock collar flush against the wheel. Mark the axle with a Sharpie right behind the collar so you don't lose your spot. Tighten the lock collar with your 5mm Allen.
4. Insert Axle Keys: Tap the keys flat into the wheel hubs using a rubber mallet.
5. Install Outer Axle Nuts: Tighten the large outer nylon nuts with your crescent wrench. (Note: If you want a cleaner look, you can trim the excess axle sticking out past the nut during your final assembly.)

Phase 7: Handlebar Controls

1. Mount the Brake Lever: Loosen the set screws with a 3mm Allen to slide the lever onto the bars. CRITICAL: Use a standard wrench, not an impact, to tighten the 6mm clamp bolts (8mm head). Tighten them evenly so the gap on the top and bottom of the clamp is identical.
2. Mount the Thumb Throttle: Use a 4mm Allen. The cap fits cleanly one way. Angle the throttle slightly downward so it is comfortable when you are in a tucked riding position. (Note: Use the long-throw cable for stock carburetors, and the short-throw cable for aftermarket flat slide carbs!)
3. Mount the Kill Switch: Using a Phillips head screwdriver, mount the toggle switch to the bars. DO NOT OVER TIGHTEN. You are threading a metal screw into a plastic housing. Run them down until they are just flush and snug.

Phase 8: Seat & Gas Tank

1. Center the Seat: Place the unit tank and the seat onto the frame at the same time to ensure they look uniform. Center the seat on the frame rails.
2. Mark and Drill: From underneath the frame, use a Sharpie to mark the four seat holes. Remove the seat and carefully drill the holes into the wood base using a 1/4" drill bit. (Be careful not to drill too deep and puncture the seat cover!)
3. Pre-Thread the Holes: Off the bike, manually run a bolt into each hole to start the threads. Then, place the seat back on the frame and mount it securely using a 13mm or 1/2" socket.
4. Drill the Uni Tank: Find the pre-marked dimple on the bottom of the tank. Drill it out with a 1/2" bit. Pop in the rubber bushing, followed by the petcock.
5. Mount the Tank: Use the supplied fine-thread bolts and lock washers. The frame bracket is slotted, so push the tank backward until it butts up perfectly against the front of your seat, then tighten it down with a 1/2" or 13mm socket.

You are Rolling!

Congratulations, your GPS Drift Quad Roller is complete! Your 5 feet of 420 chain and any remaining hardware will be used in the final step once you mount your engine and TAV system.

Now is the time to sit on it, test the steering, and double-check your clearances. Once you are happy with the dry mockup, tear it down, send that frame to powder coat, and get ready for final assembly!