Overall shot

Despite endless adjustment and an improved caliper set, I have never successfully gotten the rear disc brake on my M365 to bite early enough. After fresh calibration, they work pretty well for awhile, but it's not long before losing their effectiveness. While I expect hydraulic calipers to still require some maintenance, the big win is to feel them grip very early in the brake lever's travel to the point of locking up.

XTECH hydraulic brake calipers drastically improve grip as both brake pads move rather than just one against a fixed pad. Coupled with a wider rotor, the contact area of the pads is larger. And it's all possible with a Shimano bracket as an adapter. This modification isn't easy, but it sure isn't terribly hard either.

These three main components are:

You'll also need some hardware:

  • 3x M5 or M6 Washers
  • Button-head M5 bolt
  • ~15mm long M5 bolt

I suggest starting by freeing the rear wheel, swapping in the new rotor, and understanding how it all comes together. There's a pin that sits loosely through the caliper assembly which holds the brake pads in place. I removed it and lifted the pads lift out of the top with needle nose pliers.

The bracket has two threaded offsets for the caliper assembly. The other two non-threaded holes would be for a bike's bolts, but we'll only be using one of them. It's the one on the outward piece of the bracket. It points toward the front of the scooter and should hold the higher up brake bolt. I placed the bracket as such and held all components in place. With the calipers on and the new rotor in place, a few tweaks become apparent.

Drilling the bracket Positioning the holes

The bracket has no hole for the lower bolt— this is where to drill. I eyeballed and marked for alignment, trying to center it as much as possible.

With that done, I prepared to test mount it. For correct positioning of the pads around the rotor, you'll offset the mount with 2-3 washers on the upper bolt and 1 washer on the lower.

The existing bolts that came with the scooter won't work. One is too short and the other's head bumps into the butt of the caliper assembly. This is where to use the button-head bolt to clear the bottom of the calipers and the longer one to reach through the washers.

Washers Overall, behind

Now, there are a few important points to know. The fit is really tight. The caliper assembly just barely clears the rim, and I found it requires taking out the pads to put on or take off. I don't think this is concerning as everything does come together, it only requires some extra steps.

Clearance, behind Clearance, side

It's easy to forget the wheel's axis bolts do affect rotor alignment. Before lining up the calipers, I securely fastened the wheel.

With all that in mind, the next steps were to mount the adaptor bracket to the scooter, and the XTECH assembly to that. I spun the wheel and nudged each piece until it cleared. I then dropped in the pads and reinserted the pin. Lastly, I gently wiggled and pulled through a little more brake cable length to reach the new position of the clamp.

Testing its responsiveness just about blew my mind. This mod really does seem to be the end-all brake improvement.

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