Big wheels, big travel, big everything… apart from the price. While a bike that costs this much should never ever be called cheap, the TF03 – on the face of it at least – looks like a bargain in these insane days of megabucks bikes.
Frame and equipment: large hoops, long travel, refreshing simplicity
BMC’s Trailfox TF03 is a 150mm travel full suspension 29er. While it's not unique, it’s still quite a rarity to see that amount of travel allied to the largest wheel size. The 650b onslaught seemed to kill off the long-travel big-wheel genre just when it was starting to gather momentum.
The alloy TF03 is the bottom rung Trailfox. There’s also an alu-front, carbon-rear TF02 SLX and a full carbon TF01 XX-1 with an unsurprisingly humungous price tag.
The Trailfox has been a model name for BMC since 2007 and it’s changed considerably over the years. The first TF had 26in wheels and 120mm of travel, making it quite a different ’fox to the 2014 one.
Indeed, there’s no getting away from saying it – this new Trailfox is designed for enduro riding. Sorry, that should say enduro racing. Whereas previous Trailfoxes were ‘just’ trail bikes – and good ones – the new race genre of enduro has clearly made the designers at BMC focus on the business of getting results.
The APS floating pivot system is discreet and effective, with built in sag guide
Two things that haven’t changed much are the general aesthetic of the frame (which looks extremely BMC, with its squarish tube profiles and slightly characterless utilitarian looks), and the suspension design is still BMC’s Advanced Pivot System (APS) floating pivot system. The rear swingarm is attached to the front triangle by a pair of linkages. With such a system the designers can get the rear suspension to behave differently at different parts of the travel. They can also use the mechanical forces of the drivetrain (chain forces under pedal power) to achieve or reduce certain suspension characteristics.
This all sounds really complicated, and it is, but on the trail the APS system is one of the most discreet and forget-about-it floating pivot designs there is. It doesn’t bob or stiffen up that much. It doesn’t mind giving up its last few millimetres of travel or bottom out noticeably. It’s also a refreshingly simple system to set up – adjust air pressure until the built-in sag marking lines on the top rocker link line up and then set the rebound to your tastes. Done.
Fox provides both the fork (Float 34 CTD) and shock (Float CTD BV Performance) and they felt balanced and well suited to each other. We ran both units on the Trail setting, as this was firm enough for climbing but still gave out the travel when descending without being overly soft and unsupportive, as the Descend setting can feel.
Fox suspension units front and rear are well matched, but run them in Trail
The frame is as well executed as the suspension system. The designers have worked hard to come up with a design and layout that ends up just looking so normal. Everything the rider needs is sorted – loads of standover, fuss-free cable routing, good mud clearance and bottle mounts that work.
The 74-degree effective seat angle is spot-on for comfortable efficient climbing, but a lot of jiggery-pokery has gone on to achieve this seat angle with 29in wheels without ending up with lengthy chainstays. The Trailfox’s are 434mm – only a few millimetres longer than some 26in wheel bikes.
The usual problem on full-suss 29ers is what to do with the front mech. BMC’s opted to mount it on to the swingarm. It never missed a beat during testing.
The almost entirely Shimano SLX drivetrain and brakes work brilliantly. Faultless shifting, taut chain feel, powerful but modulation-a-go-go braking.
Our test bike came with a chainstay-mounted chain retention device. It's similar looking to other designs, namely Bionicon’s dinkier version, we weren’t initially sure whether it was necessary. But during the test, when we ended up hurtling at insane speeds over shattered rock gardens, it was nice to know it was down there.
The chainstay-mounted guide helps secure the chain in the rough
The 55mm Easton Haven stem and 750mm BMC flat bars were a great combination. Some riders wished for even wider bars – but they always do, don’t they? We were rather smitten with 750mm, they gave the bike a bit more hup-hup and interaction than a set of plough-on 780mm bars.
The only niggles we had with the bike’s kit were the DT Swiss M1900 wheelset and Continental tyres. They weren’t quite tough enough for the abuse that the rest of the bike happily puts them through. The tyres’ sidewalls weren’t supportive enough for hard cornering or braking and the wheels needed their spokes tightening on more than one occasion. Try to swap to more capable rubber and get the wheels hand-tensioned when the bike goes in for its first service.
Ride and handling: fit for purpose – and then some
The TF03 is brilliant at its job. It climbs efficiently. It’s not a light bike and until it gets upgraded with some choice lighter components it’ll never be hugely sprightly up the hills. But it is incredibly grippy and stable. We spun out way up some improbable inclines on the TF03. We like the neutrality of the rear suspension – it has just a nice balance of dig and give on climbs.
The TF03 is a comfortable place to be during long days in the saddle and it came as no surprise to us that it absolutely screams down descents. Big wheels, long and slack geometry, a lot of suspension travel – it’s a formula made for letting fly downhill. We expected it to be sluggish and a handful in the tight stuff but it wasn’t. We certainly had to grab it by the scruff of the neck and dictate what we wanted but that's a great thing, not a negative, in our book. It needs to be ridden aggressively – at 100 percent all of the time. It’s a race bike in a funny sort of way.
The Trailfox massively rewards hard riding
It was only an uninspiring ride when the pilot was being uninspiring, which is worth factoring in. It’s not an everyday trail bike and can feel characterless and muted if it’s being ridden steadily. Calm, contouring, straight trails are not where it wants to be. The TF03 needs more amplitude in its environs.
The Trailfox needs to be ridden against a ticking stopwatch, whether it’s a real one or just in the rider’s head. All that matters is that you're ‘up for it’, because the Trailfox begins to give out its rewards when it’s being ragged to the limit on terrain that’s worthy.
This article was originally published in What Mountain Bike magazine.