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2025-07-05 15:36:34 +00:00

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+++ categories = ["build"] tags = ["bicycle"] date = 2025-07-04T19:00:00-05:00 description = "" draft = false slug = "bicycle-brakes-replacement" title = "🚲 Bicycle Brakes Replacement" author = "nicholas" +++

⚠️ Bad Brakes

The brakes on my Trek FX 2 Disc Gen 3 are not working well, and are of low quality generally. The main problem is the front brake lever piston push rod that is meant to convey the force of the brake lever to the hydraulic fluid came free from its socket. The brake still works, provided that the linkage is carefully positioned. Otherwise if it is out of its socket, it will not link the brake lever to the hydraulic lines and there will be no braking. This is adequate, most of the time (except that the brakes need to be bled constantly and are just not very good brakes), but brakes are too important to be merely adequate, most of the time. Both the front and rear will be replaced. Again, not totally necessary since each of the brakes still technically work.

{{< image src="images/rush-piston-push-rod-broken.JPG" caption="Push rod disconnected" >}}

When we bought this bike used on Facebook Marketplace, we did not notice the brakes were different than those specified on the Trek website.

From the Trek website:

Trek reserves the right to change specs, models, and prices without notice.

Supposedly, due to supply chain issues during the Covid-19 era Trek was forced to substitute the (preferred, presumably) specified Taiwanese Tektro HD-R280 brakes for a little-known Chinese brand, formerly Taiwanese brand: Rush, a brand of Ningbo C.STAR Technology Co. LTD (??? 😟).

{{< image src="images/rush-ningbo-cstar-technology-co-ltd.png" caption="😟" >}}

👎🏻 Old Brakes

{{< image src="images/rush-brake-front.JPG" caption="Rush brakes - front" >}} {{< image src="images/rush-brake-rear.JPG" caption="Rush brakes - rear" >}}

New Brakes

I will not replace them with the spec'd Tektro HD-R280. Instead, as far as I can tell, I will be upgrading to Shimano MT201-UR300.

{{< image src="images/shimano-mt201-ur300.png" caption="Shimano MT201-UR300" >}} {{< image src="images/shimano-brake-front.JPG" caption="Shimano brakes - front" >}} {{< image src="images/shimano-brake-rear.JPG" caption="Shimano brakes - rear" >}}

📋 Process

I intended to document the process. I forgot.

🧾 Notes

The process went smoothly except in a couple of steps. I had a few problems:

  • Tape failing while pulling the string and hose through the frame (hose coated in mineral oil hydraulic fluid makes for weak tape adhesion).
  • String not pulling from the very center of the hose, pull angle offset from the hose angle. This offset was large enough and the margins afforded by the cable routing grommet small enough, that the hose could not pass through.
  • Sometimes the layer of tape was too thick.

My final solution involved inserting a metal coat hanger wire into the hydraulic hose, bending it into a loop and compressing the free end of the coat hanger wire into the hose, fastening the wire to the hose with friction. This allowed me to tie a string to the loop and pull the string through the frame with relative ease. It solved all of my problems. Since I had not trimmed the hydraulic line to size yet, I had much more hose than I needed and could afford to sacrifice some of it in compressing the metal loop into the hose.

  • Mineral oil somehow made it onto the brake pads. This caused obnoxiously loud brakes. Solved by dunking the pads in isopropyl alcohol.

Done.

🚴‍♂️ Bike Specifications

Applies to all sizes unless listed separately


Frameset

Component Specification
Frame Alpha Gold Aluminum, DuoTrap S compatible, internal cable routing, flat mount disc, rack & fender mounts, 135x5mm QR
Fork FX Alloy, flat mount disc, rack mounts, 405 mm axle-to-crown, ThruSkew 5mm QR

Wheels

Component Specification
Front Hub Formula DC-20, alloy, 6-bolt, 5x100mm QR
Front Skewer 130x5mm QR, ThruSkew
Rear Hub Formula DC-22, alloy, 6-bolt, Shimano 8/9/10 freehub, 135x5mm QR
Rear Skewer 152x5mm QR
Rims Bontrager Connection, double-wall, 32-hole, 20mm width, Schrader valve
Tires Bontrager H2 Comp, wire bead, 30 TPI, 700x35mm
Max Tire Size 700x38mm (without fenders), 700x35mm (with fenders)

Drivetrain

Component Specification
Shifter Shimano Altus M2010, 2x9 speed
Front Derailleur Shimano Acera T3000, 34.9mm clamp, top swing, dual pull
Rear Derailleur Shimano Altus M2000, long cage
Crank Forged alloy, 46/30, chainguard, 170mm length
Bottom Bracket Sealed cartridge, 68mm
Cassette Shimano HG200, 11-36T, 9-speed
Chain KMC X9
Pedals Bontrager City Pedals
Max Chainring Size 1x: 42T, 2x/3x: 48T

Components

Component Specification
Saddle Bontrager Sport
Seatpost Bontrager alloy, 27.2mm, 12mm offset, 330mm length
Handlebar XSM: Bontrager alloy, 31.8mm, 15mm rise, 600mm width
LXXL: Bontrager alloy, 31.8mm, 15mm rise, 660mm width
Grips Bontrager Satellite
Stem XSM: Bontrager Comp, 31.8mm, Blendr compatible, 7°, 90mm
LXXL: Bontrager Comp, 31.8mm, Blendr compatible, 7°, 100mm
Headset 1 1/8" steel threadless
Brake Set Tektro HD-R280 hydraulic disc, flat mount, 160mm rotors
Max Rotor Size 160mm front & rear

Weight

Component Specification
Weight (M Size) 11.73 kg / 25.87 lbs
Weight Limit 300 lbs (136 kg) — includes bike, rider, and cargo

Additional Notes

  • Trek reserves the right to change specs, models, and prices without notice.
  • Due to supply chain issues, compatible substitute parts may be used.
  • Weights listed are based on pre-production painted frames and may vary in final production.