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Riders waking up to advantages of 29-inch mountain bikes

By Pete Gauvin

Big wheels in their element. Photo by Anna Siebelink

One needs only to glimpse a monster truck show to know that big wheels roll over objects easier. So why have mountain bikers stuck to one wheel size for nearly three decades, one that’s three inches smaller than a standard road wheel nonetheless?

It seems quite counterintuitive: big wheels for smooth surfaces, smaller wheels for rough surfaces. But that’s how it’s been, and perhaps that’s the primary reason why the bike industry and riders have been cautiously slow to recognize the advantages of larger wheels off road.

That reluctance has begun to erode, however. “29ers,” as they’re known for their larger 29-inch wheels, have negotiated the technical switchbacks to the summit of industry acceptance. Nearly every major bike manufacturer now offers at least one 29er model, and parts, from tires to suspension forks, are readily available.

Now that the supply trail has opened up, the bikes are picking up momentum in the marketplace and on trails nationwide – and momentum, as most anyone who’s ridden a 29er will attest, is one of their best attributes.

Age group racers and single speeders were some of the first to embrace 29ers. They realized that the best way to smooth out the trail is not with expensive, complicated suspension systems (not that they don’t help), but with a few extra inches of wheel radius (and maybe some suspension, too, but less critical than with 26” wheels). Now avid recreational riders are catching on to 29ers.

Speaking of wheel radius, the 29-inch wheel size is a bit misleading. The rims are actually the same size as 700c road wheels. But with a knobby tire the outside diameter of the wheel is close, but not quite, 29 inches.

Inches sminches. I count myself as a 29er convert because of the way they ride. In fact, I can’t imagine ever buying a 26” wheeled bike again, no matter how revolutionary or how touted the suspension system is. If I was determined to go full suspension, I’d go with a 29-inch model. But hop on a quality 29er and you may not see the need.

For the past year, I’ve been riding a steel hardtail 29er with front shocks (see the adjoining review on the Niner M.C.R.), primarily on the rough, rock-strewn trails around Truckee and North Lake Tahoe. From steep uphills on loose singletrack to granite stair-step drops, the 29er takes them in stride. With the 29er, I ride stronger, faster, longer and more comfortably.

And it’s been good for my muscular-skeletal health, too. When I finish a joint-rattling ride, the norm around Truckee, I don’t feel nearly as pummeled. (Certainly, the vibration-dampening Reynolds 853 steel frame helps too.) And I’ve not gone over the bars once on my 29er, which used to be a semi-regular occurrence for me on my 26” bike (now relegated to commuter use, kayak shuttles and happy hour excursions).

The big wagon-like wheels (the pioneers, after all, relied on taller wheels to settle the West) just aren’t as prone to falling into a wheel-trap or getting spooked by sleeping trail goblins. It helps, too, that my center of mass – I’m a wiry 6-foot-2 – is lower relative to the axle height of the wheels, putting me in less of a perched ass-over-iron launch position. Keeping my keister on, or just above, the seat is good for long-term health.

Particularly if you are over six feet tall, 29” wheels make great sense. But many smaller riders are won over by them, too. Single speeders swear they can climb hills that they could not on 26” bikes because the larger wheels provide a bigger contact patch for better grip and are less perturbed by rocks and such in their path. On sandy, loamy trails the wheels float higher and are less prone to washing out. On downhills, the rolling momentum and directional stability of 29ers means they aren’t deflected as easily, adding confidence at speed, allowing perhaps for a little more – speed.

Chris Sugai, co-founder of Niner Bikes, a small manufacture out of North Hollywood that makes nothing but 29ers, boldly says that if it weren’t for the fact that many racers are sponsored by companies which push 26-inch bikes, most of them would be racing on 29ers.

Perhaps some day they will. Meanwhile, they might want to encourage their sponsors to check out a monster truck show next time it’s in town.