First look | Are Growtac’s £350 Equal mechanical disc brakes a viable hydraulics alternative?

Machined aluminium, colourful calipers with lots of cool details

Robyn Furtado / Our Media

Published: March 13, 2023 at 12:00 pm

Growtac’s Equal mechanical disc brakes are positioned as a premium option, claimed to offer the holy trinity of optimal braking power, lever feel and actuation.

Until now, the Japanese brand has predominantly manufactured indoor rollers, clothing and small accessories.

Although mechanical disc brakes typically lack the sheer grunt of a hydraulic disc brake system, they are favoured by some cyclists who claim they are easier to maintain, particularly in a touring scenario.

Paul Components’ Klamper has long been regarded as the pinnacle of mechanical disc braking, alongside the TRP Spyre.

The Equals are constructed from machined aluminium and are offered in an array of colours to make them stand out on your bike – gold, grey, red, blue, black and silver.

The Growtac Equals retail for a heady £350 / $350 in their flat-mount variant, or £390 / $390 for post-mount calipers.

The lightest mechanical disc brake caliper?

These calipers are seriously light. - Robyn Furtado / Our Media

At a claimed weight of 135g per caliper, the Equal is positioned as one of the lightest mechanical disc brakes on the market.

On our Scales of Truth, we weighed the front at 138g and the rear at 148g, including an adaptor.

The calipers can be used with both 140mm and 160mm disc brake rotors, although the rear adaptor is required if you’re using the latter. Growtac says you’ll need 7 to 11mm of the bolt protruding from the non-driveside chainstay.

The Equal is only available for short-pull levers – sorry mountain bikers.

The brake cable takes a satisfyingly direct path to the pinch clamp. - Robyn Furtado / Our Media

The actuator arm turns on a pivot on the outside of the top face of the caliper. This layout means the cable doesn’t take a tight turn through the caliper, which should result in a better lever feel.

A danger zone graphic on the actuator arm acts as a visual indicator if the tension needs adjusting as brake cables stretch over time.

There’s a metal barrel adjuster to adjust cable tension. This is locked in place with a locknut.

Just a single-piston

There's plenty of adjustment for when you align the brakes. - Robyn Furtado / Our Media

The Equals use a single-piston design. This sees one moving disc brake pad paired with a static pad.

As you pull the brake lever, the moving pad contacts the rotor. It will then bend the rotor until it contacts the fixed pad.

Compared to a dual-piston brake (such as the TRP Spyre), this layout generally offers less powerful braking, worse modulation and wears your pads unevenly.

That said, the class-leading Klampers also use a single-piston design and from what we’ve heard and read, the Growtacs are touted as a great performer, so we will withhold judgement on the design until after the testing period.

What’s in the box?

Growtac says you can easily take the caliper apart to service it, and provides instructions on its YouTube channel. - Robyn Furtado / Our Media

As well as the two calipers and rear adaptor, Growtac supplies a pair of its own-branded road and mountain bike cables in the box.

Also included are two lengths of compressionless and non-compressionless housing.

The quality and type of cables used in mechanical disc brake systems is critical to their function and it’s refreshing that you can optimise the brake for your specific bike out of the box, rather than having to buy an after-market cable set.

You’ll want to use compressionless housing where the cables take tight curves and non-compressionless housing in straighter paths, such as where the rear cable routes through or under the down tube. This is to ensure optimum lever feel and eliminate any flex in the system.

You can use Shimano alternatives when the pads wear out. - Robyn Furtado / Our Media

When the brake pads wear out, Growtac says you can replace them with either Shimano K04 metal, K03 resin or K05S-RX brake pads. However, you’ll need to keep the pad assembly bolt supplied with the caliper because it’s unique to the caliper.

As you’d expect from the high asking price, the brakes are engineered beautifully.

Senior videographer Robyn Furtado is having them fitted to her Cannondale Synapse AL for testing.