Bike test: Bombtrack Beyond+ rigid mountain bike
The Beyond+ is a bike in the same mould as the Surly Krampus: a rigid steel mountain bike with plus tyres that’s extensively barnacled with mounts for bags, racks, bottles and mudguards. These wheels are the smaller plus size: 27.5×2.8in. It will take 29×3in wheels as well; Bombtrack’s 29×3 Beyond+ ADV uses the same frame.
With 27.5+ wheels, which have a radius ~25mm smaller than 29+ wheels, the bottom bracket is unusually low. This is a two-edged sword. When you’re standing on the pedals and freewheeling at speed, a lower bottom bracket feels more stable because your centre of gravity is lower.
But when you’re pedalling you hit the pedals on rough ground more often. Too often, in fact. Shorter (165mm) cranks would help if you didn’t fancy bigger wheels.
Aside from this quirk it’s a nicely designed, good-looking frame. There are fittings for almost everything, even a dynamo cable through the fork. All that’s missing are down-tube guides for a dropper seatpost; you’ll need bolt-in cable guides there if you fit one.
The bend in the top of the down tube is there to clear the crown of a suspension fork; a 100mm travel fork would work best as the steel fork’s axle-to-crown length is 483mm.
At 177cm tall, I’m supposedly borderline between sizes M and L. In fact the L fitted me perfectly for reach and its 15mm taller head tube meant less weight on my hands – a good thing with a rigid fork.
It rides well. The head angle is steep by modern standards but still yields enough trail, given the bike’s bump-swallowing tyres.
Those soft, wide tyres have a large contact patch, which means good traction when climbing, especially on looser surfaces where a harder tyre would scrabble and slip. Bottom gear for this 1×12 SRAM SX Eagle setup is just 17in so you can ride up basically anything. Coming down, the SRAM Level hydraulic brakes are more than sufficient for rigid-bike speeds.
Verdict
As a trail bike, the rigid Beyond+ is comfortable and engaging on anything short of black routes – despite a pedal-clattering bottom bracket drop seemingly designed for 29+ wheels. As a bikepacking bike, it ticks all the boxes save alternate hand positions.
Other options
Sonder Frontier SX Eagle Rigid £849
The rigid-fork version of Sonder’s keenly priced aluminium hardtail is available with 27.5+ wheels.
Surly Krampus £2,099.99
The original plus bike is still steel but now has contemporary geometry and more frame fittings.