Sea Otter Report: Shimano XTR Race brakes and carbon tubular wheels


Shimano is providing Race and Trail options for its high-end groups, and we got a first look at the new XTR Race components, consisting of completely new brakes and tubular (not tubeless) 29er wheels.

 XTR M987 Race Brakes

Shimano pulled out all the stops with the new brakes, incorporating new materials to create a tremendously light brake that still provides plenty of power to control the average (or above average) cross country bike and rider.


In a first for Shimano, the caliper and master cylinder are magnesium, rather than the more standard aluminum. Aluminum is a great material for master cylinders, it is relatively light and deals well with heat. Magnesium can be made lighter, but isn’t as efficient getting rid of heat. Shimano came up with all kinds of tricks to shed heat over the last few years, and added a few more to ensure heat control with the lightweight magnesium parts.

 The rotors are a steel/aluminum/steel sandwich construction, with additional cooling fins between the aluminum spider arms. These rotors are claimed to be 40 degrees Celsius cooler that a standard steel rotor under hard braking, effectively allowing a 160 rotor to stay as cool as a 180mm.  Stock pads can be swapped out for the ICE Tech finned brake pads for even more effective cooling.


Also new is a carbon fiber brake lever, a surprise from the aluminum experts at Shimano. This is a full on race group, and race bike have lots of carbon bits, nothing wrong with carbon levers, at least in my book. There’s even an aluminum clamp bolt for the brake lever to save those last few bits of weight.

All this adds up Shimano’s lightest brake ever, a claimed 40 grams less per wheel than the previous XTR race units.


XTR Carbon Tubular Race Wheels

You read that right, carbon TUBULAR wheels. Meaning you glue your tires to your rim, and in case of a flat you hoof it to the closest tech support station and get a wheel swap.


Say what you will for the suitability of tubulars for mountain bike racing, there is no denying they are fast, ride well, and weight a metric crap ton less than standard clinchers. With more on course support for high-level professional racing, racers are going to look for every edge possible.  With spare wheels nearby, things are going to get lighter and more fragile. Don’t worry, not one is coming for your clinchers.


The wheelset is under 1200 grams for the pair, with is really, really light. The rims are carbon fiber with an offset spoke bed for even spoke tension. The freehub body is titanium. Hubs will be 15mm thru-axle front and 135 or 142 rear. Not sure about tires yet, but the Schwalbe Racing Ralphs installed on the display bike seemed to fit the racy tire bill nicely. Price is $3200, plus a few more bills for tires. And putting one more nail in the 26" coffin, these wheels will be 29" only.