January 19, 2012

Why The Magura Hydro Rim Brakes Don't Matter*

Typical of the bike industry. Something "new"comes out and everyone is a twitter figuratively and literally.

Seems Magura has gone back to the future by introducing their RT8-TT hydraulically actuated rim brake.

Um, wait a minute....didn't they already do that in 1997?

Yep, Bart Brentjens rode 'em to some glory back in the day, then real hydraulic discs came out and rim based systems became antiquated.

So, why all the hubub about the "new" magura's? Honestly, I don't know!

A couple of counter weights to the media frenzy...

1. They are ugly!

Yes, they've been compared to the Campy Delta V's...

Maybe the Industrial-German-Techno version of a Delta V. And lest we forget Delta V's SUCKED at braking! Presumably the Magura's won't follow suit.

2. They are heavy!
From cyclingnews - "Not surprisingly, the RT8 TT is impressively light with a claimed total system weight of just 495g —comparable to a Shimano Dura-Ace mechanical setup when factoring in cables and housing." 495g, 250g per wheel...that's over a pound for levers, housing, fluid, and calipers. For comparison - you knew this was coming right? - TRP's new TTV weighs in at about 110g, and when paired with the RL879 lever at 77g each, puts your total weight at a paltry 187g per wheel, then add another 15g for cable and housing you're still around 200g per wheel, or about a 1/4 pound lighter.

3. They are expensive!
From cyclingnews: "Pricing for the complete Magura RT8 TT brake system is set at €599." at todays exchange rate that makes these a $773 investment in old technology...which brings me to the final reason these are irrelevant on arrival. Again using the TRP TTV's as comparison...they will likely have a retail price of around $150 per set (if we use the similarly v-brake based CX9 as a relative price point). Throw in the levers for $60 and you've still spent less than a third of the price..plenty of coin left for a new TT helmet!

4. Rim Brakes?
Why would you invest, presumably, tens-to-hundreds of thousands of dollars on a rim based system? Brake perfomance will not be impressively improved over existing options because it still comes down to the pad and the rim. The rim surface is uneven, prone to flexing, and inherently mediocre at adhesion, especially in wet conditions. Disc brakes on road bikes are coming. Now the UCI may waffle and waiver on allowing them, but they will be the standard within a few years, guaranteed!

Not to be a complete Nega-Nerd I'll give the Magura's props in two or three areas...

1. They mount on existing brake configurations according to cyclingnews. This is important b/c other systems like the TTV require post mounts and manufacturers willing to produce compatible forks and frames (which they are doing in droves since under the BB mounting is fairly standard in TT/Tri bikes, and most major manufacturers have embraced the fork mount version, but I digress).
2. They look killer under the fairing!
3. For their launch bike they chose TRP pads and pad holders, look closely....nice!

*The big qualifier - I work for TRP Brakes about 10 hours a week doing marketing so I AM BIASED


  1. A couple of minor comments:

    1. the braking performance is actually quite amazing despite being on a rim

    2. the aerodynamic advantage (~4 seconds per 40k or so) while quite small, overhwhelms the disadvantage of the higher weight (unless you are going up a huge climb of course)

    3. disc hydraulic brakes on a road bike incur a non trivial aerodynamic penalty, and based on my experience with the magura rim brake, there is just no reason to accept it on a road bike, where we don't often ride around in mud and dirt.

    I can't afford them (your point #3!) but if I could I would use them.

  2. Thanks ATC...

    RE: Performance, have you ridden either a rotor based brake on the road or a V-brake system on the road? How does performance compare in your opinion?
    RE: Aero - can you tell me where you got the 4s per 40k? I'm not doubting (well,much) just curious if they are 4s faster than a DA caliper or, more on point, a rear mount TT set up?

    thanks again!


  3. "RE: Aero - can you tell me where you got the 4s per 40k?"

    Presumably citing my tests: