If 29ers were born for XC and traditional trail riding, these are the bikes that are rewriting the rulebook

Hardly a day goes by without the release of yet another new 650b bike, with everything from XC to DH racing being covered by the latest middle-ground wheel size. It’s a very different landscape to a couple of years ago, when bike manufacturers were falling over themselves to jump on the 29er bandwagon instead.
Not every brand has been so quick to jump ship, however. Two key players pushing the boundaries of what’s possible with 29in wheels are BMC and Specialized; both produce 29ers with upwards of 150mm of travel that are raced at the highest level at the Enduro World Series. And they’re not the only ones. Niche builders such as Intense and Niner are also pushing the 29er envelope, but given that most of their frames cost at least as much as the complete bikes in this test, it’s fair to say they won’t be bringing long-travel 29ers to the mtb masses any time soon.

All Mountain test Specialized vs BMC OPENERS 16

Dust brothers… but who’s the daddy?

The similarities between the BMC Trailfox TF03 and Specialized Enduro Comp in this head-to-head go well beyond wheel size, price and travel. Both use clever front mech fixtures to provide the necessary clearance for fat tyres and 2×10 drivetrains (1×11 was still prohibitively expensive when these bikes were released). Accommodating a front mech is even more impressive when you consider that the chainstay lengths are as short, or shorter, than most of the new longer-travel 650b bikes. In fact, all of the key geometry numbers that determine handling are remarkably similar between the BMC and Specialized, even though both bikes were launched at the same time and therefore designed in complete isolation.
Other shared attributes include the use of linkage suspension designs, and while both bikes have different suspension layouts and characteristics and slightly different amounts of travel (the BMC has 150mm versus Specialized’s 155mm) both designs offer enough room to fit a bottle cage in the front triangle.
Neither bike comes with a dropper post, and although we love being able to adjust saddle height at the push of a button we actually approve of this decision — adding a dropper would probably have introduced compromises elsewhere in the spec.
So, two very similar bikes with one clear agenda: dispel the myth that 29ers can’t handle the really rough stuff. But which one does it better? Let’s find out…

Tale of the Test

Once again we were back on the M4 heading west, but instead of driving straight to the Forest of Dean to ride our favourite test tracks we detoured to Cwmcarn to sample the new trails.
We had already spent some time on the more expensive carbon versions of both these bikes in Molini, Italy, so we know what these machines are capable of in extreme terrain when extreme (or should that be obscene?) amounts of money are thrown at them. But let’s not fool ourselves; most riders’ bread and butter is regular trail riding, so we also clocked up the miles around the less rugged Surrey Hills to get a handle on what it’s like to live with these bikes day to day, not just for the odd dirty weekend away.

BMC Trailfox TF 03 review

The chassis of an all-out enduro racer married to the spec of a trail bike - £2,600

Score 7


From the very first ride, we knew that the Specialized Enduro Comp had the upper hand in this test, not least because the 160mm-travel RockShox Pike is a world away from the Fox 34 Float that comes with the BMC Trailfox TF03.

The Specialied is the clear winner in this test

The Specialied is the clear winner in this test

Tucked in safely behind the Pike, we were free to push the Enduro and the fork to the absolute limit. For anyone that hasn’t spent much time on a 29er, or has been emotionally scarred by riding a crappy one, the raw speed of the Enduro 29er is simply breathtaking.
It’s no monster truck, however. In fact, even though the supple suspension and bomber-solid frame have a distinct DH bias, the bike pedals efficiently and covers ground remarkably fast. But that isn’t what this Enduro 29 is really about. No, it’s about getting rowdy, getting airborne and smashing corners. After all, it’s hard not to enjoy yourself when the bike is doing most of the hard work for you.
So where does that leave the BMC? Trying to cover too many bases, we’d suggest. Until the recent introduction of the new 130mm-travel Speedfox, the 150mm Trailfox had to tread a not particularly fine line between regular trail riding and enduro racing. As such, BMC made some suspect decisions with the build kit. With a better fork, wider rims and softer-compound tyres it could prove to be a better option than the Enduro. Hopefully BMC will get the specification sorted for next season.
So the Specialized is the clear winner in this test — but why aren’t more brands keen to develop long-travel 29ers? Two reasons. The first is an engineering problem, as it’s a difficult balancing act to achieve the desired geometry with bigger wheels. There are also strength concerns associated with 29er frame construction, as the longer 29er forks place more strain on the head tube. As such, the weight of the bike can creep up, and that’s before you add heavier-duty tyres to go with the aggressive attitude.
The second reason, and it’s arguably even more crucial, is that bike companies aren’t just about maximising performance — they’re also trying to sell bikes. Consumers upgrading from 26in wheels right now are more comfortable switching to 27.5in than all the way to 29in — and that’s a vital incentive for bike companies to concentrate on 650b.
Still, with bikes like the Enduro 29 and Trailfox pushing the boundaries, the 29er genie is well and truly out of the bottle. We just hope that the rest of the industry recognises that big wheels have long-travel potential that hasn’t yet been fully explored.

Getting a handle on offset and trail

The BMC and Specialized have almost identical head angles, so you’d think that with similar stem lengths they’d have similar steering characteristics. They don’t, and that’s because of the difference in the offsets on their forks. The Enduro’s RockShox Pike has a 46mm offset while the BMC’s Fox 34 has 51mm. Without going too far into the nuances of steering geometry, increasing the offset reduces ‘trail’, which has a similar effect on the steering as steepening up the head angle. As a result, the steering on the BMC is lighter and twitchier than on the Specialized.