Updating Brakes Round Two

Patrick October 13, 2024

Back in mid-July, I updated the Hope brakes on my Volagi Viaje. I replaced the original RX4 calipers with the new and improved RX4+. Whereas the old RX4 used 2x14 mm and 2x11 mm pistons, Hope increased the pistons to 2x16 mm and 2x14 mm for the RX4+ calipers. I paid little attention to the pads then, but once out of the box, I immediately realized that RX4 and RX4+ calipers shared different brake pads. The original pads for SRAM RX4 calipers are 30.8mm wide. The width of the pads increased to 37.0mm for RX4+ calipers. That's a 20% size increase.

Volagi Viaje with new brake calipers. — Volagi Vuaje.

Front Hope RX4+ post mount caliper. — Front caliper.

Rear Hope RX4+ post mount caliper. — Rear caliper.

Hope RX4+ versus RX4 pads. — RX4 pad on top.

When brake pads push against a rotor, they produce friction, and the kinetic energy is converted into heat. Larger pads, just like pistons, and rotors dissipate heat better. They require less braking pressure to produce the same braking force. Less pressure translates to less pad wear. The RX4+ calipers with the massive pistons also look amazingly cool. It was therefore time to treat the Nordest Albarda to a new set of calipers. The Nordest has gone through so many updates over the years that only five things remain from the original build; the frame, the fork, the headset, the saddle, and the cranks.

Nordest Albarda with new Hope RX4+ calipers. — Nordest Albarda.

The RX4 flat-mount calipers I took of my Albarda are 5 years old. They still work and look like on day one. When I built the Marin Gestalt X12, budget-minded me used SRAM Rival calipers. They looked great in their all-black finish. The calipers have two quite large pistons but in comparison with Hope calipers, they have fairly small pads. Brake performance is good but not mind-blowing. Brake pad life is decent. They need adapter plates front and back. The calipers are made of two halves bolted together with two steel bolts. While elegantly shaped, this makes them a bit bulky.

Marnin Gestalt X12 with Hope RX4 calipers. — Marin Gestalt X12.

I retreated into the basement and replaced the SRAM calipers with the Hope RX4 calipers from my Albarda. All I had to do was cut the SRAM olives and barbs off the hoses and add the ones from Hope. In the heat of the battle, I forgot to check hose lengths. I could have shortened the front hose by another 5 to 10 mm. The Marin lost some weight (full disclaimer - I didn't weigh the two caliper pairs), gained some braking power, and looks cooler, too.

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Patrick July 19, 2024

Updating Brakes Round One

I owned a lovely set of red Formula R1 brakes since 2010. They went onto my singlespeed Niner Air9 Carbon, moved to my black 44 Kid Dangerous in 2013, and then to my 44 Marauder in 2017; fourteen years of service and still working perfectly. It was time to treat the Marauder to a new set of brakes. I was just waiting for a worthy replacement to appear on the market. This happened recently with Hope’s release of the XCR brakes in anodized colors and the option of two, or four-piston calipers. Hope is essentially the only manufacturer that still offers disc brakes in a variety of colors. The XCR with E4 calipers were the brakes I was waiting for.

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