Shimano Deore XT BR-M8020 brakes review

The XT BR-M8020 brakes are part of a long line of reliable Shimano XT stoppers, touting a claimed 10 per cent increase in braking power over the twin-pot and hugely popular 8000 XT model.

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On the bike, I could feel a marked improvement, not only in power but in the positive bite point and grab, which made inspired confidence.

However, after a few rides, the bite-point lost its consistency, wandering slightly and causing me to grab the brake lever earlier, in case it needed to be pulled further than usual.

The effect was subtle, though, and the power and positive feel was still there, it was just the lever throw needed to make the pads bite the disc rotor varied slightly when the brake wasn’t actuated for a period of time.

I had used the brake straight out the box, without trimming the cable or disconnecting the lever or caliper from the hose to reduce the possibility of introducing air into the system. I then trimmed and bled the brakes myself later on, which eliminated the air in the system causing the wondering bite. This isn't a massive issue and could just have been down to some rogue air trapped in the system despite best efforts.

Once riding, I generally found them to be superb and powerful brakes, with zero setup issues and handy and effective adjustments on the lever.

The reach is externally adjustable with a dial at the root of the lever blade, while bite point adjustment, or free stroke in Shimano parlance, needs a cross-head screwdriver to tweak. This was fine because once I had set it to my satisfaction it didn’t need readjustment.

Bleeding was also a quick and easy process, with the mineral oil being simple to handle and posed no threat to my bike's paintwork if there was a spillage.

As with SRAM Code brakes, Shimano has introduced different piston diameters on the new XT BR-M8020 brakes, with the leading edge of the brake getting a smaller piston. Theoretically, this brings it into contact quicker for improved modulation and puts more power through the trailing edge of the brake pad, which should reduce brake noise and vibration.

It certainly seemed to work well in terms of modulation because I was impressed with the lever feel and power in general, but in terms of noise it didn’t seem to help.

After a handful of rides I was dealing with some distracting squealing from the finned IceTech pads. Despite best efforts with rotor cleaner, repositioning the caliper and more, the noise wouldn’t abate. When the brakes were shifted to another test bike the problem stopped, but no other brakes I tested on the original test bike squealed.

With such a capable brake, it’s a shame that Shimano doesn’t supply spares. If your brake dies you can only replace whole levers or calipers, rather than the more environmentally friendly seal kit/replacement piston repair option.

As dealers have pointed out, by the time you add labour to the mix, replacing seals or pistons is rarely a cost-effective option, but there are plenty of home mechanics among us that are happy rebuilding brakes, but that isn’t an option unfortunately.

It has to be said, though, the warranty system on Shimano is excellent, so you are safe for two years at least.