Bike test: Diamant Mahon World trekking bike

Diamant is part of Trek’s empire, but it’s a German brand and the Mahon World is very much a European tourer. It’s an absolute beast of a trekking bike with a correspondingly high load limit: 136kg for rider, bike and luggage.

Frame & fork

The Mahon World is an all-aluminium bike with chunky tubes and square-profile seatstays. The frame has a quick-release axle, while the fork uses Trek’s Thru-Skew system. The drive-side seatstay can be split to fit a belt, because that’s what the Mahon Style Pro and Plus models come with; they share the frame.

The bike’s touring aspirations are clear from the number of bottle and luggage mounts. All the bolts have washers, which is good to see. I like the understated look of the bike.

Components

This Diamant comes with just about everything: a super-chunky Tubus front rack; a rear rack integrated with the mudguard; a front hub dynamo and LED lights; and a kickstand, which I used pretty much every ride.

The rear rack is an all-in-one structure with the mudguard, which has a hefty metal strip running up its centre. The downside to this design is that if you want to fit even bigger tyres, you’ll need a different rack.

The Shimano front hub dynamo powers LED lights, which reach maximum brightness at around 8mph. The front’s 200-lumen beam is bright enough for you to be seen, but I wanted more power for unlit routes. Being mounted on the fork crown, it picks out potholes very well.

Gearing is based around a single ProWheel chainring and an 11-speed ultra-wide-range Shimano cassette, whose largest sprocket is the size of a small plate. The chain can run at quite an extreme angle, but I never unshipped it during testing. The large jumps between sprocket sizes didn’t prove an issue either.

The 42-tooth chainring and 50t sprocket deliver a 24in bottom gear, which is low enough for casual days out, as well as commuting-type rides and trips to the shops. If I were planning a fully laden tour, I’d like a smaller chainring, such as a 38 or 36, to get the bottom gear nearer to 20in.

Braking comes courtesy of Magura four-piston hydraulic brakes. I can’t say I noticed any extra power over a dual-piston design, but the action was light and smooth, and the 180mm rotors make the most of the power.

The 32-spoke wheels and high-end Schwalbe tyres major on toughness and durability. I’m a big fan of the tyres’ reflective strips, which are very effective at night.

Ride

The Mahon World delivers a regal and imperious ride. You’re in a nicely upright position that puts little strain on your body, and the slack head angle makes for relaxed handling.

You notice the bike’s weight when climbing but it’s very stable, thanks to its long wheelbase (1,117mm) and high trail figure (95mm). The gearing and braking deliver consistent control at all times, and it’s a confidence-inspiring descender once you’ve crested a hill; you’ve got to love hydraulic disc brakes!

Long, leisurely days out are this bike’s forte. The tread of the 50mm tyres copes well with broken roads, light gravel and unsurfaced canal towpaths, so you’re not restricted to the tarmac touring.

Verdict

Straight out of the box, the Diamant Mahon World has everything you need for composed, everyday rides. A lot of care has clearly been put into its design and execution.

With racks and guards, it’s ideal for commuting, big days out and leisure riding. The wide tyres and – to my surprise – Brooks B17 saddle keep it comfortable.

I’d ride it exactly as it is for day-to-day use, only switching to a smaller chainring for a fully laden tour. Overall, though, it’s a very good trekking bike that’s well priced, given the quality of the components and equipment.

Other options

Oxford Bike Works Model 1 £1,729+

A more traditional-style British tourer with triple chainrings, a Reynolds steel frame, V-brakes and a lovely finish.

Rockrider Travel Bike ADVT 900 £1,799

Similar-looking, well-equipped 1× machine from Decathlon that’s even weightier – but it does have a mighty 170kg maximum load.

First published in Cycle magazine, June/July 2026 issue. All information correct at time of publishing.