Riding the 29er

There’s a new (or relatively new) arrival on the MTB block.

Several manufacturers, including Gary Fisher, are now producing mountain bikes that are in essence a generic hard-tail mountain bike frame with larger 700c road bike size diameter wheels.

These bikes are commonly referred to as Big Wheels, or 29ers, which is the approximate diameter of the wheels from tread to tread.

When Fisher initially approached me about trying the 29er I wasn’t exactly excited.

I hadn’t even heard of it before, and as far as I was concerned their Sugar-1 full suspension bike was the ultimate ride.

How could those larger, heavier wheels possible be faster?

What about the maneuverability of the big wheels over my favorite terrain – tight and rugged single track?

And what about adjusting to a totally new ride feel?

Well…  there are a few benefits to Big Wheels, too.

The first thing I noticed is that once a 29er is that, at speed, the bike really wants to stay there. The larger wheels preserve the momentum of the bike.

This can be noticeably helpful on off-road terrain, whether it is for bowling over loose rock, roots, or short, steep rises.

Another feature of the big wheels is the smooth ride.

Compared to a conventional 26” hard tail, the 29er rolls over obstacles with less jolting, as the larger wheel reduces the “angle of attack” between the wheel and the object. This characteristic also serves to preserve the momentum of the bike.

When the terrain turns to sand, snow and mud the 29er makes use of its larger contact patch (the surface area contacting the tire tread and trail).

This ‘snowshoe’ effect helps prevent the bike from bogging down while providing more traction for acceleration.

Having raced the bike in the snow against the world’s best winter triathletes at the Canmore ITU race, I’ve experienced these benefits firsthand 

One of the most important features I look for in a new bike is stability at speed over rugged descents. 

The big wheels are great for this.

The key to riding faster descents is in steering as straight a line as possible. This also entails absorbing larger bumps.

Big wheels aid in both these areas, due to the gyroscopic effect they maintain the direction the bike’s being steered in.

The bike goes where it’s told, and the bigger wheel decreases the jolting effect that can throw the bike offline.

Will the 29er take on a full suspension when the descents are really rugged?

Probably not, but it will easily beat a hard tail.

The 29er also has the same wheelbase as a regular 26” bike, so turning radius is the same.

The head angles, bottom bracket height, and seat tube angles are also identical. So steering and maintaining balance over the bike in tight, rugged single track feels much the same as a traditional mountain bike.

Another noticeable feature of the 29er is the lower center of gravity.

When combined with the larger wheels this produces a very stable feeling.

However, that same lower center of gravity on the 29er makes for harder whee 

The rider must adjust for this by either pulling harder on the wheelie or going a little faster and bunny hopping with both wheels.

So how do the big wheels climb on a variety of surfaces and gradients?

The 29er is a hard tail so, for a really rugged climb, full suspension wins out.

The 29er does have its place on the climbs. It shines over steep and/or loose sections where the larger contact patch provides more bite.

The big wheels are also at their best on less steep and smoother grades where speeds are higher and more constant, such as pavement sections and dirt/access roads.

The 29er of course has its limitations. Most obviously on tight single track the larger, heavier wheels will be slower.

A full suspension is still the way to go when the terrain is really rugged.

The 29er is at its best on faster, more open courses where a conventional 26” hard tail would otherwise be the choice.

Currently 29” wheels are banned for use in the World Cup mountain bike competition, but allowed for NORBA and XTERRA.

With some of the world’s best at both these events riding 29ers this year we’ll soon see what they are capable of.

A few adaptations on the part of the rider helps bring out the full potential of the 29er.

Author Mike Vine is the 2000 XTERRA Canada Pro Champion and the 2002 XTERRA Saipan Pro Champion.