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Trek Checkpoint AL 4 review

Alpha Trek

Our rating 
3.5 out of 5 star rating 3.5
GBP £1,250.00 RRP | USD $1,600.00
Trek Checkpoint AL4 with fenders

Our review

All-road versatility with refined road manners for a fine riding machine
Pros: Frame design and mounts, hydraulic Tiagra groupset
Cons: Chirpy mudguards
Skip to view product specifications

The second rung on Trek’s Checkpoint ladder is this AL 4, which shares an entry-level Alpha 200 aluminium frame with the lesser-specced AL 3. Up front is a carbon fork and tapered alloy steerer with gravel riding in mind.


But can a gravel bike really pass muster as an all-weather, all-season machine? I think so. With a frameset built to take a pounding, heaps of tyre clearance and mounts for almost anything, the Checkpoint is well-featured; when appropriately configured, it should be versatile enough to take you almost anywhere.

Trek Checkpoint AL 4
Neon lime ’guards will keep you seen.
David Caudery / Immediate Media

As well as the obvious full mudguard mounts, there’s a third bottle cage mount beneath the down tube, which is useful for a spare bottle on long rides.

The two cage mounts within the main triangle each offer high or low fitting positions, allowing for rider preference and frame bag fitment.

Behind the stem is a top tube mount for a fuel/essentials bag and the Checkpoint can take racks front and rear.

The stem accepts Bontrager’s Blendr compatible accessories, such as lights, camera and GPS mounts; the NCS mudguards on my model even have a Blendr mount at the rear for an extra lighting position.

Every tube, except the round seat tube, is heavily shaped. The top tube is flattened, the head tube sculpted to resemble some of Trek’s other bikes and the seatstays create an arc between the seat tube and rear dropouts. The fork is subtly curved, too, but there’s no IsoSpeed on this model.

It’s nice to see a complete groupset with no shortcuts and the Checkpoint AL 4 has Shimano’s 10-speed Tiagra. A 50/34 compact chainset with 11-32 cassette offers a range suitable for road and beyond.

Hydraulic discs with 160mm rotors give perfectly modulated, powerful braking with minimal lever pressure. The levers boast Shimano’s usual ergonomics, and no matter how badly timed my actions were, the drivetrain shifted sweetly every time.

The Control Freak cable routing system pulls them all in to the top of the down tube, but my knees clashed with the free cables when riding out of the saddle.

Shimano Tiagra 50/34 chainset on Trek Checkpoint AL4
A 50/34 compact chainset offers a range that’s suitable for on- and off-road.
David Caudery / Immediate Media

From the Bontrager Arvada Comp saddle, my 56cm Checkpoint AL 4 felt like a perfect fit. The saddle itself was comfortable and the Bontrager bar and stem stiff enough when under load, without transmitting much road buzz.

Although the semi-compact frame exposes plenty of the alloy seatpost to flex, a carbon seatpost upgrade could improve seated comfort.

The Checkpoint is great on the open road, its 32mm Bontrager R1 tyres measure 33mm. With 70psi inside they give a helpfully cushioned ride. Their smooth central band rolls efficiently while the textured shoulders seek out all the available grip in slimy corners.

Cyclist riding a Trek Checkpoint AL4 road gravel bike
The Trek Checkpoint AL4 is great on the open road.
Russell Burton

Bontrager’s wide Affinity rims support the tyres well and can be simply converted to tubeless for a smoother, more secure ride. They accelerate willingly, not rapidly, but with enough go to make attacking hills an option.

Through technical twists and turns the Checkpoint feels just like a road bike, its 72.2-degree head angle (size 56cm) and 73.5-degree seat angle, 61mm trail and 1,021mm wheelbase are a fine balance of stability and agility and I had no toe overlap issues with the mudguards.

They give excellent coverage with built-in flaps, but I did experience regular chirping from them. For the price, though, the AL 4 is a well-sorted package.

Trek Checkpoint AL 4 geometry

  • Seat angle: 73.5 degrees
  • Head angle: 72 degrees
  • Chainstay: 42.8cm
  • Seat tube: 47.8cm
  • Top tube: 55cm
  • Head tube: 15cm
  • Fork offset: 5cm
  • Trail: 5.9cm
  • Bottom bracket height: 27.5cm
  • Bottom bracket drop: 7.6cm
  • Wheelbase: 1,023m
  • Stack: 59cm
  • Reach: 38cm
  • Mud Guards: £40 / $60 / AU$100

Product Specifications


Price GBP £1250.00USD $1600.00
Weight 11.32kg (56cm) – As tested
Brand Trek


Features Extras: Bontrager NCS mudguards
Handlebar Bontrager Comp VR-C alloy
Tyres R1 Hard-Case Lite 32mm
Stem Bontrager Elite, Blendr compatible
Shifter Shimano Tiagra, short reach, 10-speed
Seatpost Bontrager approved, alloy
Saddle Bontrager Arvada Comp
Rear derailleur Shimano Tiagra, long cage rear
Headset FSA integrated sealed cartridge bearing
Front derailleur Shimano Tiagra
Available sizes 44, 49, 52, 54, 56, 58, 61cm
Frame 200 Series Alpha Aluminium
Fork Checkpoint carbon, tapered alloy steerer
Cranks Shimano Tiagra 50/34
Chain Tiagra HG54 10-speed
Cassette Shimano 11-32 10-speed
Brakes Shimano Tiagra hydraulic disc, 160mm rotors
Bottom bracket Shimano RS500 68mm threaded external
Wheels Formula RX hubs, Bontrager Affinity Disc rims