I recently spotted a gravel bike you’ve probably never heard of at Eurobike — the Moulton XTB. A new gravel bike with all the modern gravel features you could possibly want.
Featuring Columbus steel tubing, a full suspension chassis, small wheels with clearances for large tyres, tan-wall rubber, a gravel-specific 1x drivetrain and the ability to pack the bike down small for travelling, this could be the perfect gravel machine. And, it comes with some fairly unique looks, too.
Moulton’s are radically different designs that were conceived out of a need for efficient and comfortable transport — free yourself of any conception of this looking like a 'normal' bike. The XTB is based on the original AM-ATB from 1988, claimed to be the world’s first full-suspension mountain bike, and updates it in a modern gravel incarnation.
All about stiffness
Moulton bikes have a relatively unique concept, based primarily on separating the stiffness of the chassis and optimising it for handling and then adding suspension for improved comfort.
The frame is designed to be as stiff as possible, with a space-frame construction to provide direct and accurate handling.
The small 20in wheels are claimed to be stronger, stiffer, improve handling, and be quicker to accelerate, as well as exhibiting less aerodynamic drag. I do question how good they will be rolling over rough terrain though…
Along with that, running high pressures is claimed to improve rolling resistance (though there is some debate about high vs low pressures and how they actually play out in the real world) and make for a more efficient ride.
Full suspension on a gravel bike
Bigger brands certainly think full suspension on a gravel bike could work, but on a Moulton, it's an absolute necessity to provide comfort with the stiff frame and small wheels. The rear uses a single pivot design damped by an elastomer shock.
The fork uses a Leading Link suspension design, which mounts the front wheel on a separate ‘link’ in front of the main fork legs. It appears that both damping and ride height are adjustable with this system.
Interestingly, the original design of this suspension was closely related to and inspired by the work Alex Moulton did on the rubber suspension system of the original Mini car. A good while back, the BikeRadarreview of a Moulton bike found the suspension to be quite effective.
Gravel approved gear
The XTB is built up with a SRAM Rival 1 groupset. which is proven on many other gravel builds. It does not, however, feature disc brakes, instead opting for V-brakes.
The bike rolls on high-volume, 20in tan-wall Halo MXR tyres. These are designed for BMX really and I don’t imagine they’ll have the best grip off-road — I also assume it will be fairly hard to find a good selection of gravel tyres for this bike.
The frame is constructed from custom Columbus tubing, and the meticulous brazing on the space frame is admittedly rather beautiful.
There’s also a full complement of accessories available for the XTB if you decide to get one. That includes racks, bags and mudguards.
The final killer feature is the frame can be split in the middle to take the bike apart for transport, leaving you with a diminutively sized case that shouldn’t incur any excess baggage fees.
Pricing and availability
While the bike is featured on Moulton’s homepage there are no details about pricing or availability yet.
This is a fairly bizarre-looking and niche bike, but there’s a part of me that can’t help but have a soft spot for the (over) engineered design of these curious-looking things. In all fairness, BikeRadar has reviewed Moulton road bikes in the past and come away feeling very positive, so dismissing this one at a first glance may be unfair.
I can’t quite see this being used for the ultimate of gravel-gnar (images of small wheels falling into ruts and holes abound) but nonetheless, the XTB is likely a rather capable utility machine.