Tested
TRP G-SPEC E-MTB DISC BRAKE
£160 (Rotor £35)
SPECIFICATION Weight: Caliper 342g (front) • Rotor 205g (203mm) • Contact: upgradebikes.co.uk
E-bikes typically weigh around 8-10kg more than regular trail bikes, so once that juggernaut gets trucking, stopping it can be tricky. Which is why most come fitted with 200 or 203mm rotors front and rear. The bigger rotor offers more power and better heat dissipation, so the brake doesn’t fade when you need it most. Obviously, some manufacturers don’t think this is enough, which is why 220mm rotors have started to appear. TRP’s take is to offer a big disc but also a thicker one with its G-Spec E-MTB brake – this has gone up from 1.8 to 2.3mm. Since there’s more metal, it’s a bigger heat sink, and it also shouldn’t warp as easily, which can happen to thinner discs.
I’d like to say TRP has increased the pad/ piston spacing to accommodate the extra thickness but I don’t think it has, or by that much. TRP brakes always had a lot of pad clearance – it’s what I liked about them – but I noticed a little bit of rubbing with the new rotor and getting it centred was a little trickier. Either way, once the pads had bedded in, rubbing wasn’t a problem.
The four-piston Evo caliper is pretty similar in size and shape to the one used for the G-Spec Gwin brake, apart from the surface finish, which is now smooth rather than ribbed. It has lightweight hybrid pistons, contains sintered metallic pads, which are top loading, so can be replaced easily. These are also held in place by a chunky fixing bolt with a 3mm Allen head and kept apart by a stiff spring – small details, but they make a difference.
With its wide blade and square body, the brake lever also shares a lot of the same architecture. There’s no contact adjustment, but it does have a big indexed dial to adjust the reach – no faffing about with a long ball-end Allen key here. And if you don’t like it, it’s only held on with a tiny grub screw.
There are two 2.3mm rotors available for the G-Spec E-MTB – a floating design with a stainless steel braking surface attached to a lightweight aluminium carrier for
