TPE17: Hope Tech shows flat mount RX4 four-piston disc brake calipers for SRAM, Shimano

Written by Tyler Benedict Mar 23, 2017 4:51 p.m. ET

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At Eurobike last year, Hope Tech introduced one of the most interesting upgrade options we’ve seen: Replacement hydraulic disc brake calipers for both Shimano and SRAM road groups.

Now, the Hope RX4 road disc brake calipers gain a flat mount variant with distinct front and rear versions since they don’t use any adapters. That means they’re only for 160mm rotors, a conscious decision because they say 160mm’s are a “more sensible size” since they dissipate heat better and will work better on long descents. The longer pad of their four-piston design also helps shed more heat faster.

The Shimano ones (shown) get larger pistons because their master cylinder is designed for their larger pistons. SRAM is smaller, so the pistons are smaller.

Available in April, post mount versions are available now. All six colors are represented. £95 for flat mount, £75 for the post mount we saw at Eurobike last fall along with the rest of their new road collection.

HopeTech.com

Tyler Benedict

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Tyler Benedict is the Founder of Bikerumor.com. He has been writing about the latest bikes, components, and cycling technology for almost two decades. Prior to that, Tyler launched and built multiple sports nutrition brands and consumer goods companies, mostly as an excuse to travel to killer riding locations throughout North America.

Based in North Carolina, Tyler loves family adventure travel and is always on the lookout for the next shiny new part to make his bikes faster and lighter.

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Not for Me

7 years ago

WOW! So many questions

fred

7 years ago

sure are purdy. think i’ll hold out till they make a six pot version. no way 4 pistons is adequate for my riding style.

greg

7 years ago

Reply to fred

EnduRoad, bro!

Wendigo

7 years ago

I love Hope brakes but why do i want to use their caliper?

myke2241

7 years ago

Reply to Wendigo

Another option beyond Simmy and SRAM I suppose. Could provide more braking power. I think this is more of a factor for cross and gravel. It would be cool in the mtb world too. Provided there are no ill side effects.

typevertigo

7 years ago

Reply to myke2241

Maybe Hope can get past Shimano and SRAM’s issues. SRAM recalled its road disc brakes because of seal failure not too long ago, while Shimano has had issues with its ceramic pistons cracking and leaking mineral oil – and sometimes even leaving riders with no braking at all, like what happened with BikeRadar’s Ben Delaney.

Beat_the_trail

7 years ago

Reply to typevertigo

The SRAM issue pre dated their road disc, it was with their levers on the road hydro rim brake.

mateo

7 years ago

Reply to Beat_the_trail

It affected the disc brakes as well (same lever for both), but that is well in the past. No issues with current SRAM hydro brakes (road or MTB).

Tomi

7 years ago

Reply to Wendigo

Because anodized parts are big again.

7 years ago

I’d to know the weight of the caliper alone.

Rob

7 years ago

Reply to me

According to hope website: Weight: 123g for a Post Mount Shimano complete caliper

BMX

7 years ago

Excuse my stupidity but how does a calliper with 4 pots retract the pads the same amount as a pad with 2 pots? Do the 4 pots have the exact same amount of volume as the 2 pots? If so they would be very small pistons.

Rod Diaz

7 years ago

Reply to BMX

It’s not stupidity, it’s skepticism – you answered your own question – it depends on the dimensions of the individual pistons.

I bought these (the post mount version) because I love Hope and my brakes ping a bit with my main wheelset (Shimano calipers, Ultegra, with Shimano discs. Another wheelset with slightly thinner rotors doesn’t) and thought it was worth a try. They (Shimanos)didn’t make a sound new, but a couple of seasons of CX piling the bike in a trunk will do that to you.

With the new Hope calipers the rear brake stopped making any sounds, the front still does due to a noticeably warped rotor. That’s with a newly bled line with very little travel to actuate the brake. So maybe they are unto something?

Another difference is the much wider pad vs. the Shimano. Don’t know if that’ll have any effect. I haven’t ridden them hard yet, Spring has not sprung here yet and it’s fatbike for a few more weeks.

TheKaiser

7 years ago

Reply to BMX

You are correct that 4 pot calipers generally have smaller pistons than 2 pot calipers, assuming the same master cylinder size is used. Even if the volume of the 4 pot is the same as a 2 pot, it can potentially produce more power, because the center of pressure is redistributed closer to the outer edge of the rotor. Keep in mind too, that the springiness of the piston seals is what retracts the pads, for the most part, and that will play a big role in the amount of pad retraction, regardless of the number of pots/volume in the caliper. Whereas, the ratio of master cylinder piston size to caliper pot piston size/volume will have more of an effect on the amount of lever travel before the pads engage.

haromania

7 years ago

You’d think that at some point companies would run out of badass ideas/products, but they never do. These look great.

Jérémy Dascotte

7 years ago

Does it means it could be compatible with Shim’s and Sram’s mtb brakes???

Beat_the_trail

7 years ago

Reply to Jérémy Dascotte

I think so, I’m fairly sure the Shimano road calipers are the same as the LX mountain calipers, not sure about the SRAM stuff

Rod Diaz

7 years ago

Reply to Beat_the_trail

Probably, but wouldn’t you be better off using the Hope brake already tailored for MTB? Not that I don’t like tinkering, but there’s way more nice options for MTB hydraulics than road.

If anything I’d guess the reservoir and volume of liquid pushed in a road caliper is smaller than in an MTB brake, so it might act too fast and strong unless you can modulate that. That’s another advantage, most MTB brakes are more adjustable than my Shimano road levers.

1 piece caliper

7 years ago

Hope brifter next please.

wheels

6 years ago

Due to curiousity of RX4 i read at different forums.
What i did note was one thing. Those running Shima mtb brakes and now Hope, or vice versa, all say Hope has a completely different way of coming on with braking compared to Shima.
So it seems this pretty much, part from braking faster, harder or better concerns how we actually like our brakes. Not necessary that one is better than the other.
Shimano uses 4 piston disc brakes to, Zee and Saint. But those are more or less aimed at Enduro/ Down hill aso.

What i can’t stop wondering, more moving parts, higher risk of retraction isssues, damged pistons and leaks. Perhaps so,, or perhaps not..Just saying..