I’ve been wanting to post something on wheel size for mountain bikes for a while. Thing is that even though I own bikes from 26″ to 29″ and a fatbike which is a 26″ rim with a 29″ external diameter – I just don’t have enough time on enough bikes to justify my opinions well. It’s really not fair to compare a 26er 6″+ full suspension bike to a 29er 4″ travel hardtail or a rigid fatbike. How do you separate out the differences in geometry and suspension from the differences in wheel size?
I’d love to own long travel full suspension bikes in 26er, 650B and 29er wheel sizes for back to back comparisons, but that would require a ton of $$ I don’t have. 😦
What I will say is that wheel size does matter. There are distinct pros and cons, but they have to be evaluated in the context of the specific bike design. You can’t just pick a wheel size and throw down a blanket statement that it’s going to be better than another wheel size. So these days you can’t afford to ignore wheel size if you are buying a new mountain bike. Especially if you keep your bikes for a long time.
I think it’s safe to say that the differences aren’t worth upgrading from a bike you own and love. Any trail you can ride a 29er or a 650B bike on you can ride a 26er on. It you have an existing bike you want to tweak I’d spend the $$ on new tires for an easy high bang for your buck performance boost.
If you’ve been paying attention to any media outlets in the mountain bike world you know 650B is coming on strong. They are also calling it 27.5″ even though it’s actually closer to a 26″ wheel/tire than a 29″ wheel/tire. It looks like a lot of brands will have 650B bikes in the line up for 2013 and I suspect almost all of them will for 2014.
Based on my limited experience with bigger wheels it looks like 650B will be popular as it blends some of the 29er roll over ability with a smaller package that is easier to design into a long travel frame and retains the playful feel of the 26″ format. “All Mountain” style bikes with 6″-7″ of travel are the ideal candidates for the new wheel size.
My Santa Cruz Nomad sports wheels that measure 26.75″ with 2.4″ tires on Velocity P35 rims. Sharon’s Nomad with 2.3″ tires on narrower rims measures 26.25″. It’s amazing that the Continental Trail Kings on my bike are so much bigger than Sharon’s Nevegals. Given the size of my wheel/tire combo I don’t have any huge urge to upgrade my mountain bike to 650B.
Having said that as I ponder a new mountain bike for 2013 or 2014 I’ll restrict my choices to 650B machines. I don’t think it will be long before the all mountain category, where my interests lie, will be made up of a majority of 650B designs. This has the added benefit of giving me an incentive to keep riding my Nomad while more 650B options hit the market and these designs have a product cycle to mature. I’m not in a rush to roll on 650Bs, but when I do get a new rig it might as well have ’em.