dgasmd

Just saw this today, but there has been a couple of articles leaking info on them. The one thing they don't clearly mention is the "benefit" over standard cable brakes. I can clearly see the benefits of discs on road bikes, but the benefit of hydraulic completely escapes me. It is not like there isn't more than plenty powerful brakes on the market now. Heck, the limit on braking is not strength of the brakes but rather the grip once you hit the brakes. In other words, we can lock wheels very easily now, so how is this going to be of benefit over cable actuated brakes? I am just not seeing the obvious maybe, so point it out to me please..........

dnuzzomueller

From what I understand this is more useful for TT and Tri bikes since a hydraulic system would allow for multiple brake levers in varying locations.

AEO

I think magura is the only maker to offer hydraulic rim brakes for MTB.
and no, I don't see the point in hydraulic rim brakes. I mean, sure, they will be better than cable actuated rim brakes or cheap disc brakes, but you have to pay quite a lot for their custom setup and this sort of negates cost issues.

ericm979

Magura hydraulic rim brakes are popular for the rear brake on observed trials bikes. They're very powerful, which is important in trials since so many of the moves involve keeping the rear wheel locked.

I think the advantage for TT bikes is that the brake can be made more aerodynamic than cable brakes and still be powerful enough.

rpeterson

You can take a brake hose and make all sorts of fun 90 degree turns inside a frame and still have the brake work just fine, you can't do that with cables. So it's possible to have the brake hose go anywhere and everywhere and be as invisible as possible.

That's the biggest benefit for TT bikes, cause currently the aero brake offerings really suck. Go ride something like a Kestrel 4000, or try using the rear brake on a P4, it's just pointless, they hardly work.

AEO

For TT bikes, I'd be a bit worried about crushing a carbon rim while braking with hydraulic rim brakes...

Dannihilator

I can't wait for $60 brake pads. Magura stuff tends to be overpriced. They used to sell an adapter for one of their disc brakes that was $80.

rpeterson

The braking is only as strong as it's designed to be, do you really think they would release a high-end bike with brakes that would crush the rims the first time you had an emergency stop? They would have killed their test riders long before it got to market.

FeartheReign

I would guess the "tease" is for hydraulic disc brakes, as opposed to rim brakes. Disc brakes move the rolling mass closer to center of the wheel, improving acceleration and deceleration. Also if you take the braking surface off the rim, you can now have a lighter rim... I've never personally ridden carbon rims but I have heard that the braking power is less than inspiring, discs fix that problem too. Just my guess.....

Dannihilator

But put a ton of stress on the spokes.

Pros:
Better performance when wet.
Lever feel is much better than what you get on a cable actuated brake.
Pending on where the tabs are on the rear, much more areo than a conventional road brake.

Cons:
Servicing them is a royal pain in the rear, you would have to buy a service kit to bleed the brakes.
Lever fade: When the brakes get hot the fluid boils and you can lose the brakes until they cool off.
Where the hose is routed will have to be exact, outside of the gradual bend from the levers, any odd route could kink the hose. That will greatly affect the performance of the brake.
There will be another thing to check on the trueness of. Rotors have to be checked once in awhile to see if they are true.

I <3 Robots

"Hydraulic integration has been a massive point of speculation recently. It is confirmed that Magura is the new partner working with Cervelo to now have the world’s only fully integrated hydraulic brake system available on the road today. The center bolt mounted Magura RT8TT brakes weigh a svelte 495g (calipers, hydro hose, fluid, levers and all mounting hardware.) This is by far the lightest brake configuration available for any road bike. A very interesting piece of trivia is that one meter of hydraulic hose WITH oil weighs 5g, while the same length of brake housing and cable is 70g. The RT8TT system is a closed system, much like the original Magura HS 33 brakes."

"Along with the increased modulation and power comes further aero benefits. The Magura front brake even without the aero cover found on the non-UCI P5 is still about twice as fast as a standard brake caliper (wind tunnel and CFD tested.) This brake setup will fit all wheel sizes and handlebar diameters, and will be available for aftermarket sale for your TT/Tri bike sometime later this year. Unfortunately right now, there is no option to use the Di2 brake/shift lever with the Magura RT8TT system."

https://www.bikerumor.com/2012/01/18/...ed/#more-38927

mconlonx 

Do we know yet if we're talking hydraulic disk or hydraulic rim brakes yet...? Post above seems to indicate rim brakes and plenty previous assumed as much, but I thought the next big thing was supposed to be disk brakes?

jimc101

Magura haven't made a road hydraulic brake for years (the HS66 was their last), but the RT-8 TT (Hydraulic Rim) looks nice, even if it has a very specific market, that of Triathalons and Time Trials. https://www.magura.com/roadbike/

For their benefits, on the road, they were around before Dual Pivot was standard & before STI / ergo shifting, both of which made the HS66 redundant unless using bar end or down tube shifters , off road, they were around before v-brakes, and were better than Canti's, but with v-brakes, then disc coming on, they have really been outclassed, and are only useful if your frame doesn't have disc mounts.

For the cost of pads, they used to be expensive, but with other 3rd party suppliers now making them, there are plenty of other options, for the RT-8 TT, this appears to use standard road cartridges (probably SRAM/Shimano fit)

They do seem to be spec'd on a lot of tourers in Germany still though.

mconlonx 

Rim brakes, apparently...

Improved braking with Magura's RT8TT hydraulic system

Perhaps the change for the P5 that will be met with the warmest reception from both TT riders and triathletes is the complete overhaul of the braking system. Riders have often lamented the P4’s somewhat archaic rocker-actuated cantilever setup, but this has now been superseded in every way by the new, custom designed RT8TT hydraulic brakeset from German company Magura.

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Having a hard time imagining the benefit vs. hassle on these suckers...

danvuquoc

How reliable are hydraulic brake systems compared to cable systems, and what kind of maintenance is required?

Realistically, even in my car I'm not overly worried about brakes failing, but something about it on a bike seems more alarming.

jimc101

Have been using several sets on MTB's over the last 10 years, apart from pad swaps, have done nothing else for maintenance, and don't anticipate anything in the future.

slims_s

+1... they practically don't require maintenance. No cable stretch, when the pads wear the pistons push further so you don't need to adjust anything.

mikepwagner

I am guessing that this is the big one - though maybe "elasticity" would be a better word for what I am thinking about.

I am not referring to the permanent stretch where the cable get longer over a period of time.

I am thinking of the temporary elasticity in the cable when you apply the brakes - the cable stretches a little bit.

The hydraulic fluid doesn't compress as much as a cable stretches.

Bob Dopolina 

This.

giantcfr1

If you get them, you will be the centre of attention with the coffee shop set.