GT Grade Power Series AMP review

The GT Grade AMP has some potent genes: the carbon-framed Grade won our Gravel Bike of the Year title back in 2020.

That said, the Grade AMP isn’t built around the compliant carbon Grade's template. Rather, it’s constructed based on the aluminium Grade, which in non-electric form tops out at £1,450.

However, in testing the GT Grade AMP has proven to be one of the best-value off-the-peg electric gravel bikes available today.

GT Grade Power Series AMP frameset details

The GT Grade Power Series AMP features an alloy frame, complete with a carbon fork.

The geometry carries over from the Grade to the Power Series range. This means my large test bike gets a sporty endurance ride position, with a 608mm stack and 395mm reach combined with a relaxed 71-degree head angle and 73-degree seat angle.

This results in a bike that’s designed to be full of pep, even at its 14.8kg weight.

The frame is capable of being much more than ‘just’ a gravel bike. With mudguard and rack eyes front and rear and bento box mounts, it’s easy to see the AMP as a brilliant commuter bike, as well as a weekend adventurer.

GT Grade Power Series AMP specification

GT has packed some good kit into the AMP for the money, and even though it's cheaper than many of its electric gravel bike rivals, it’s not outclassed.

The 1x GRX groupset, complete with the GRX 810 rear derailleur, is Shimano's highest-tier offering.

The front chainring features 40 teeth, with a 12-speed 11-42 tooth cassette offering plenty of range.

The brakes are Shimano’s GRX 600 hydraulic models.

The bike comes with WTB Resolute TCS 700 x 42c tyres, fitted to GT-branded alloy rims.

A Formula CRX-512 front hub and Mahle ebikemotion X35+ rear-hub electric bike motor offers the anchor points for the alloy spokes.

The motor

The ebikemotion X35+ motor that drives the bike is a relatively simple system.

A 250W motor in the rear hub is powered by a 250Wh battery hidden in the down tube.

It’s controlled by a simple top-tube mounted, one-push button.

Its stated output is 40Nm of torque, which is shy of comparable systems such as Fazua’s Evation. That motor has a claimed 60Nm pulling power, and can be found on rival electric gravel bikes such as Cairn’s E-Adventure 1.0.

Ebikemotion comes with clever app support. Here, you can custom-tune the power levels and keep a better eye on power reserves.

You can even link it to a heart rate monitor, so it’ll up the assistance to help you keep your heart rate under a certain level, if desired.

GT Grade Power Series AMP geometry

GT Grade Power Series AMP ride impressions

The GT Grade AMP accelerates with ease and feels responsive even when the assistance is powered down.

Riding on tarmac on my way to pick up the trails, I didn’t feel hampered by the Grade AMP. Even the 42mm-wide gravel tyres didn’t feel especially sluggish, and their weight is negated when you hit the dirt.

The bike's off-road manners really impressed me.

It’s balanced and lively when the going gets rough and the handling response is quick without any odd quirks. It tracks straight in the rough and its stability is impressive at speed.

If there is a low point in the ride, it’s at the front end. I enjoyed the shape of GT’s adventure-style bar with its slightly flared shallow drop – but it's very stiff.

Combined with a stiff carbon fork and firm alloy frame, I found it to be energy-sapping on a particularly rocky stretch where the quality bar tape couldn’t quell the vibrations pumping up my forearms and tiring my shoulders.

Shifting is swift, though I did find a bit more chain chatter than SRAM-equipped bikes.

I welcomed the chain guide fitted in place of a front derailleur, keeping things in check and adding a little peace of mind.

Overall, braking from the GRX 600 hydraulic system is excellent. Controlled, dependable, and powerful, it’s everything you need to halt a 14kg bike safely.

The WTB Resolute TCS 700 x 42c tyres are a great choice. The tight tread rolls on the tarmac and grips really well on dry dirt.

Ridden through sloppy mud, they perform okay – if you stay seated and use the power on tap to make progress. I recommend refraining from the instinct to stand and use your body weight to ride tricky, muddier sections.

The alloy seatpost does its job, but could be an area you target for upgrading with a more compliant carbon unit.

However, it’s topped by one of the best-value, best-performing saddles I’ve come across in recent times in Fabric’s Scoop. I’ve spent many, many an hour on this design and never had a complaint.

Although the X35+ motor system delivers ‘only’ 40Nm of torque, it rarely feels underpowered compared to Fazua’s 60Nm Evation setup (the key exception being when you put a Fazua system into ‘Rocket’ mode).

Controlling the motor is easy, with a series of colour-coded illuminations of the ring around the top-tube button.

The ringed LED shines white when switched on, then green for ‘low’ assistance, orange for ‘medium’, and red for ‘full’.

This indicator also shows you an approximate indication of the power left in the battery.

White indicates a 75 to 100 per cent range left, green 50 to 75 per cent, orange 25 to 50 per cent, red 10 to 25 per cent, while flashing red indicates less than 10 per cent remaining.

The only real downside to the system is it cycles through modes upwards only. I often found myself in the lowest assist mode and wanting to turn the power off on flat sections of road, but having to go up through all the modes to do so.

The range impressed me. Tested on mainly gravel surfaces, with just shy of five miles of tarmac in total, the Grade AMP delivered 98.73km / 61.35mi with 928m / 3,045ft elevation, displaying a flashing red ring by the time I’d got home.

On a more mixed ride (featuring gravel, tarmac, towpaths and bike paths) the range rose to 100.5km / 62.5mi.

GT Grade Power Series AMP bottom line

I’ve come away from riding the GT Grade AMP hugely impressed. It outperformed my range expectations and it’s a blast to ride.

I’d look to swap in a set of the best gravel handlebars in order to get something more comfortable, and a more compliant carbon post wouldn’t go amiss. However, as an affordable off-the-peg e-gravel bike it’s hard to beat.