Powerful, but sensitive to heat: Shimano XT brakes (4 pistons) fail the lab test

Conclusion from Dimitri Lehner, BIKE editor

If it says XT on it, it's XT inside - as the Japanese have shown us in this comparison test. The 2026 version of Shimano's mid-range four-piston brake still offers plenty of power, a crisp pressure point and feels great in the hand. We do not recommend the Ice-Tech hardware - so everything is as usual.

Technical data: Shimano XT model year 2026

Easy to dose? Only with a sure instinct!

"You can feel the disc in your fingertip" - Shimano XT has perfected this inimitable lever feel. Experienced riders love it: they can get up close and personal with the disc, know exactly where they are in the lever travel and immediately feel how the brake reacts.

Even a slight pull beyond the initial contact is enough to apply the brakes.se anchors. No grinding, no slow approach - the pads grip immediately. This makes the XT the surgical tool among mountain bike brakes. Conversely, this also means that in the hands of inexperienced riders, the XT is just as out of place as a scalpel in a first aid course - to put it bluntly, of course.

And then there is the magnetic lever feel with the high breakaway torque. To guide the pads to the disc in a controlled manner also requires sensitivity. In direct comparison with the XT, it is most difficult to fine-tune the initial bite.

Lever ergonomics as a brake booster

As differentiated as the response behaviour of the Shimano may be, there is unanimity when it comes to ergonomics: no lever feels as good in the hand as the XT. The pronounced hook at the end of the lever receives the most praise. On long downhills, when the hand force decreases, you can hang onto the lever with all your strength and always squeeze enough braking power out of the system.

Too bad for hand giants: If you turn the lever width all the way up, the short lever is too steep and the ergonomics deteriorate. Theoretically, the Shimano XT also scores with a free travel adjustment via Allen key - but even after several turns, you hardly notice any difference.

Size matters...

...at least in our test procedure for measuring braking force. The standard stipulates this: The force must be applied 25 millimetres from the end of the lever. For the stub lever of the Shimano XT, this means almost the centre of the lever. And since physics cannot be tricked, the XT is literally on a shorter lever in this test.

The competition with longer levers achieves the same braking performance with significantly less manual force. In the laboratory, the XT thus suffers a severe defeat. In practice, however, where you pull on the outside of the lever, the braking power is completely sufficient.

The heat shock

However, there is no excuse for the defective brake disc. Under the high thermal load during the dry brake test, the sandwich construction of the Ice-Tech rotor warped so badly that we had to abort the test prematurely.

The combination of Ice-Tech disc and Shimano's organic pad compound also delivers the worst friction values in the wet and falls behind. The cooling fins of the pads rattle in the caliper.

The BIKE rating

How BIKE tests disc brakes

Our impressions of the character, modulation and handling come from practical tests. We determined the maximum braking power and thermal stability in accordance with the DIN standard on the roller test bench of the brake manufacturer Magura.

Braking force test in the laboratory

To ensure that the brakes can deliver their maximum performance on the test bench, the test standard prescribes a defined braking procedure. All models must maintain a constant braking force of 200 newtons over 20 braking intervals in order to reach temperature and rule out pad fading during the brake force test.

Only then does the actual test of strength begin. It consists of three brake applications per force applied to the lever. It starts at 40 newtons of manual force. The test stand increases the force on the lever in 20 Newton increments until the brake reaches its maximum lever travel. Each brake undergoes this procedure twice: once in the dry and once in the wet. During wet running, the disc is continuously wetted during the entire measurement.

For optimum comparison, all models run with 180 mm discs. The pad compounds always correspond to the standard equipment. The manufacturers were allowed to select the discs themselves - if several options are available in their own range - in favour of braking performance. For uniform comparative values, we carry out the brake force test and the heat resistance test with a fresh pair of pads and a new brake disc.

For the evaluation of braking performance in the laboratory, we only use the results at 80 N manual force. In this range, all models still deliver practice-relevant values below the 600 N threshold, especially during dry braking. Above this level, there is a risk of rollover under ideal grip conditions.

Heat resistance

As a second hurdle in the laboratory, all brakes have to pass a standardised heat resistance test twice. After all, the candidates should decelerate reliably even under high thermal loads.

The programme includes three endurance brake applications of five minutes each per test run. Shortly after each interval, an abrupt control brake application follows, which shows whether the brakes are still decelerating properly despite the heat. Finally, the test bench calls up the required minimum braking force three times. All brakes passed this test.

Practical test

No test bench can measure how a brake develops its power off-road, how it reacts to low manual forces, how finely it can be metered and how it feels in the hand. This is where experience counts.

And our testers have plenty of them: over 100 complete bikes go through our test procedure every year. Our editors therefore know most of the brakes inside out. In addition, two testers rode all the brakes in this test in direct comparison on standardised bikes with identical setups.

Competitor models in the test