What’s so great about 29er Mountain Bikes?

What are the advantages of a 29er on the trail?

If there’s anything that seems to be right in biking fashion at the moment, it’s 29er mountain bikes. I can’t move for 29er articles, 29 bikes in the local shop and 29er fanatics trying to convert me at every turn. So, hey, I thought, why not add to the cocophany and write even more about them? Why not indeed.

Seriously though, I had no idea really what 29ers were for, and possibly neither have you. What’s the advantage of a 29er? In what situation would you want to use a 29 bike? Well, recently I endeavored to find out the answers to all of these questions and, generous guy that I am, here I’ll share what I found out!

What is a 29er Bike?

This is simple at least: a 29er is nothing more than a mountain bike that’s built to run on 700cc wheels. “Woah!”, I hear you say, “Isn’t that getting dangerously close to lycra-clad, tarmac-fetish cycling?” Well, yes, a little. Mountain bike rims are traditionally 26″ in diameter, while road bikes run on 700cc, or 29″ rims. 29er bikes are attempting to profit from the advantages of bigger rims by building stronger, wider road-bike sized wheels and taking them off-road.

What are the Advantages of 29er Mountain Bikes?

So, to the 29er bike advantages. Why bother to increase your wheel size? After all, the whole bike needs adjusted to accomodate the extra wheel diameter. What do you gain by going 29er:

• An increased ability to roll over obstacles. The larger wheel can clear rocks, roots, steps and badgers more easily thanks to the reduced striking angle. Basically, on a 29er you can roll over a rock with less effort and less lost speed than on a 26″ mountain bike.
• Increased ground clearance. Thanks to the larger wheels your bottom bracket, chainset and pedals are further from the ground and therefore you’ll grind over rocks and logs a bit less often.
• Thanks to the greater diameter of your wheels, they have a much greater angular momentum than their smaller 26″ counterparts. This basically means they carry speed through the rough stuff much more effectively, acting as if they’re much more heavy and harder to slow down than smaller wheels.
• If you’re big, bigger wheels will suit you better. Pretty common sense this, but worth mentioning – many taller rider struggle to find frames to fit. With bigger wheels comes a more natural geometry of frame for bigger guys and gals.
• An higher feeling of stability. Many people claim that putting 29ers on a bike increases it’s stability, feeling a lot less twitchy than the equivalent 26″. This could be thanks to the aforementioned increased angular momentum, or the increased weight, but apparently a 29er just feels more planted on the trail.

What are the Disadvantages of a 29er Mountain Bike?

What are the disadvantages of 29 bikes in mountain biking?

So, there seem to be a few good reasons to get a 29er above. A smoother, faster, easier ride – all good huh? Well, not quite – the big wheels bring with them a few drawbacks:

• Firstly, it’s still pretty hard to find a good choice in 29er bike rims, 29er tyres and all the other normal wheel paraphanalia that you can find so much of in good old 26″. This is changing of course as more manufacturers jump on the 29 bike bandwagon.
• 29er wheels are heavier than their 26″ counterparts, simply because they’re bigger. This increase in weight makes 29er bikes slower to accelerate and harder to stop than an equivalent 26″ bike. Even the forks have to be slightly longer than on a traditional mountain bike thus adding further weight.
• Due to the increased angular momentum of the wheel that I mentioned above, 29 bikes require more force to turn the wheel. This is exacerbated by a larger contact patch with the ground. All this means that it just takes a little more effort to turn your bike, making cornering slightly less responsive.
• Thanks to the increased length of the spokes and the larger forces due to increased diameter of the rim, 29er bikes tend to suffer from more flexible rims, making the ride seem a little more ‘wobbly’ to use a very technical term.

Conclusions on the 29er Conundrum

After a fair bit of reading, I’ve come across a number of different opinions on 29ers, and I suspect it’s very much the same as any other bike rivalry – hardtail vs full-sus anyone? The most common opinion that I’ve found, though, is that 29ers just don’t have the nippiness, the flexibility and the fun factor that their smaller cousins have. Yes, 29ers take some of the bump and grind out of the trail. Yes, a 29 bike feels faster on the uphill and more stable on the downhill. Yes, you’ll catch yourself on less roots and rocks.

But… more often than not riders just seem to prefer the acceleration, responsiveness and pure fun of a 26″ bike. It makes sense I suppose. Hands up: who out there got into mountain biking for the stability and comfort it offered? No-one…? Thought so…

Give me your opinions though – have you ridden a 29er? Tell me what you thought? Have you been converted? I’d love to hear.

Image Credit: Flickr placid_casual