Are mountain bikes getting too stiff?
New editor Steve ponders the question
Nobody wants to ride a frame that behaves like two unicycles joined with string every time the front wheel hits the deep end of a squirrel’s toe print. And nobody sane misses the days when stiff chassis were beyond many manufacturers. But has all that hydroformed and carbon-weave strength gone too far? While lateral strength adds much-needed tracking precision and cornering stability, excessive vertical strength just ends up fatiguing and even unbalancing the rider… meaning less control, not more.
Just man up and get on with it, some might say – race bikes and cross-country (XC) hardtails are supposed to be stiff. Uncompromising. Manly. But how does making riders suffer make them faster? Without the rider, the fastest bike in the world will just fall over and lie still. The rider is an intrinsic component. So it’s stupid to ignore their needs.
Take the carbon Niner Air 9, for instance, which tech ed Justin Loretz has been running for the last year. “It’s near the top of the stiffness scale,” he says. “When I ride it, I’m thinking about how long the ride’s going to last, because it’s uncompromisingly direct chassis prematurely wears me out. Whereas when I take the Seven Sola – a compliant titanium hardtail that’s the antithesis of the Niner in concept – I’m thinking, ‘How long have I got?’ The frame’s working with me, not against me. So which one, in the real world, is actually more efficient? For me it’s the less-stiff one.” The Niner is a stunning bike, make no mistake, but it’s a design that asks a lot of you.
Interestingly, there’s a parallel in motorcycle racing. For decades the quest has been to build stiffer and stiffer chassis to contain the ballooning power outputs of MotoGP bikes (they’re past 250bhp now…). After years of frighteningly bendy frames, the materials – aluminium and then carbon beam frames – have caught up. And gone too far. Even Valentino Rossi couldn’t get on with Ducati’s insanely stiff carbon ‘airbox’ chassis, as while it was technically the best solution – according to computer data – human riders couldn’t tell what it was doing (Casey Stoner was the sole exception, and having seen him ride in person, we can confirm the guy is a superhuman robot). MotoGP manufacturers now invest heavily in controlled flex, designs that bend in one plane but not others, to allow riders not comfort, but that all-important, performance-enhancing feel.
Mountain bikes are now in a similar position. Frame stiffness can surpass a rider’s ability to make it pay off. Trek seems to have realised this with its road bikes – it’s just released the Domane, which has a seat tube that’s partially decoupled from the top tube for comfort on cobbled events. And if roadies are realising comfort isn’t a dirty word, surely it’s time hardtail mountain bikes got the same attention.
This entry was posted on Tuesday, April 17th, 2012 at 11:39 am and is filed under Blog, What Mountain Bike. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.