IIIPRO 6R Road Bicycle Hydraulic Disc Brake CNC Integrated Caliper Road Bicycle Line Pull Brake Modified Hydraulic Disc Brake

The IIIPRO mechanical-to-hydraulic brake converter kit offers an affordable way to upgrade mechanical disc brakes to hydraulic performance, with reviewers praising its braking power and value, but noting installation complexity, orientation sensitivity, and potential compatibility issues.

Pros

Very affordable (under £50) and includes two converters and both brake calipers1
Impressive braking performance close to genuine hydraulic systems, far better than mechanical disc brakes1
Allows running hydraulic calipers with mechanical shifters, providing a neater system than running cables all the way to the caliper2
Lightweight (137g per adapter vs 266g for Giant Conduct)1
Good power and modulation with a nice solid brake feel1
Decently made one-piece aluminum units1
Split reservoir design handles different orientations well1

Cons

Installation requires finding placement for two separate units and can be messy to position neatly; may interfere with computer mounts or bike lights1
Requires specific bleeding technique and no bleed nipple on calipers (just a threaded port), making installation trial and error1
Lever feel not as sharp as genuine hydraulic brakes; slightly more lever travel and hint of sponginess; requires squeezing slightly harder for top-end braking force1
Requires 160mm rotors, not compatible with 140mm rotors1
No proper documentation included1
Durability is unknown due to aluminum construction and small delicate seals1
Not the lightest and chunky to mount into handlebars2
Flat mount design may not be compatible with all bikes2

Key Facts

Weighs 137g per adapter1
Uses standard BH59 hydraulic fittings1
Split reservoir design with two chambers and rubber diaphragms1
Requires 160mm rotors (does not support 140mm)1
Includes dual-piston brake calipers1
Ceramic pistons in calipers2
Flat mount design2
Aluminum construction one-piece units1

Sources

1
Trace VeloThis AliExpress Bike Gadget is Pretty Incredible...
2
Tom Bowers CyclingI Tried 5 AliExpress Bike Products – Deal or Disaster?

Reviews & Ratings

Trace Velo

21:42

This AliExpress Bike Gadget is Pretty Incredible...

The reviewer tests the IIIPRO hydraulic brake converter kit, which converts mechanical shifters to hydraulic disc brakes. They state the kit includes two aluminum converters and dual-piston brake calipers for under £50. The reviewer finds the braking performance impressive, very close to genuine hydraulic systems and far superior to any mechanical disc brakes they've tested. They successfully install the kit on a winter training bike, noting the need for proper orientation and bleeding technique. While not as easy to install as integrated systems, the reviewer is very impressed with the value and performance.

November 11, 2025Watch on YouTube

Tom Bowers Cycling

15:24

I Tried 5 AliExpress Bike Products – Deal or Disaster?

The reviewer briefly mentions the IIIPRO Bicycle mechanical line pull brake converted to hydraulic brake modified parts but does not provide detailed analysis.

July 07, 2025Watch on YouTube

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