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Enhanced rear caliper from an atv

A week ago, I was inspired to install a rear caliper on my pit bike (since it didn't have one at all). This led to trips to stores, price comparisons, and so on. I chose a reasonably priced yet efficient caliper from a Chinese 250cc quad bike (the set included the caliper, hose, and a handlebar-mounted brake master cylinder), essentially a complete kit I needed. The cost was around 2000 rubles for the set, plus 1000 rubles for an extended braided brake hose to ensure the entire setup fit properly (for example, the original caliper from a TTR125 costs 2500 rubles, the master cylinder 2500 rubles, and the hose 1000 rubles), resulting in significant savings... but oh my gods!!!

The caliper bracket didn't fit the original mount because the bracket was almost one and a half times larger than the original, and replacing the original with the existing one was not an option, in my opinion, as it didn't suit the existing type of mounts on the rear swingarm. The solution is simple and clear to everyone - we improvise...

More precisely, we will improvise an adapter from the original mount to the existing one. For this, we need a gate mounting bracket (angled, 3 to 5 mm thick), 4 M8 bolts, and 4 nuts for them, as well as a set of washers for precise adjustment of the caliper's offset, a drill, 8 and 10 mm drill bits, a metal saw, and a welding machine (if you are strong enough to bend a 5mm plate, you won't need it).

Let's begin...

  1. Take an "L" shaped plate and apply it to the purchased caliper's mount, checking the dimensions from one mounting point to another, and drill them with a 10 mm bit (there will be a 2 mm gap, allowing for precise adjustment and fitting of the caliper in the future).
  2. Determine the required size from the edge of the caliper bracket and cut everything off! Then flip the second cut part and adjust the adapter for height! I ended up with a "Z" shape.
  3. Weld everything thoroughly and clean it up! In the end, we have an adapter bracket.
  4. Attach the bracket to the caliper you want to install, screw it on, and fit it to the original pit bike bracket. Then ask a friend to squeeze the brake lever (by this point, it's advisable to have everything assembled and the brakes bled, though we wait with the caliper) and position the adapter plate in the desired location, then drill through it! Spare no effort, drill, or anything! (P.S. also drill with a 10 mm bit).
  5. Drill the original plate with an 8 mm bit (so the bolt sits straight). For perfectionists, I can suggest a 6 mm bit and a tap to cut threads in it... but I chose nuts, faster and easier.
  6. Choose a second free spot and repeat steps 4 and 5.
  7. If you did everything correctly, tighten the adapter plate and the original mount with bolts.
  8. Align the caliper as you like (due to the 2 mm expansions in all the holes of the adapter plate, our adjustment range is a free play of 2 cm).
  9. PROFIT!

P.S. I didn't specify dimensions as they may vary for each pit bike! Good luck to everyone! And in the end, let's admire the mess and the half-assembled CRZ)))