In addition to its stopping performance, the RT 8TT is remarkably easy to install and use. The calipers attach to any standard brake mount with a standard brake bolt. The width can be adjusted to fit rim between 17mm and 28mm wide by turning an easily accessible bolt with a 2.5mm hexagonal wrench. This range of rim widths is wide enough to cover every wheel we are aware of. Magura doesn’t yet produce brake shoes (the part that holds the pad) or pads, but the brake arms take any standard brake shoe. A set of Shimano or SRAM brake shoes will mount to the RT 8TT and brake pad angle can be adjusted to match any wheel.
In addition to the width adjustment, the brakes have a quick release switch for easy wheel removal. Should the rider forget to reengage the brakes before jumping on the bike, the brake will automatically reengage itself.
Magura says their complete braking system—calipers, levers, and the connection between the two—weighs 495 grams and “one of the lightest” cable systems weighs 519 grams. They explain that a meter of housing and cable weighs roughly 70 grams, but an equal length of their hydraulic line and fluid weighs only 50 grams.
Shimano Dura-Ace Di2 riders will have to sacrifice their brake-mounted shifters or splice an additional shifter into their system to retain the ability to shift while riding with hands on the basebar. Other than price, the inability to use these Di2 shifters is about the only drawback we can find to these brakes.
Magura doesn’t yet produce a splitter that would allow for a third brake lever that could be installed on the aerobar extensions.
The brakes are only available with aero brake levers for now, but Magura product manager Stefan Pahl says, with a smirk on his face, that they will offer road-compatible versions “not too far in the future.” Magura will also release a cheaper version called the RT 6TT that is functionally identical to the RT 8TT but heavier.
The brake lines must be bled periodically to remove any air that makes its way into the line, but these brakes should require less service than cable brakes. They must be centered using the brake bolt only. There is no fine lateral adjustment of the pads.
The RT 8TT will come exclusively on the Cervélo P5 until April 1. On that day, Cervélo dealers will receive components for aftermarket sale at the kingly price of $750 a set, without pads or brake shoes. Dealers that do not carry Cervélo will have access in June and other bike companies will be able to spec the brakes as part of their complete builds in 2013.
Follow Aaron Hersh on Twitter @Triathletetech.