B+ Monkey

Despite what my wife might say about my wardrobe, I try to keep up with some trends. While my dress pants are mostly unfortunately pleated, I did take the dive and order up some 27.5+ wheels for my Karate Monkey. Everyone is saying that these "B+" wheels are the Next Big Thing. The theory is they'll combine the traction and comfort of a 29+ wheel with the the agility of a standard 29er, while being able to fit in most 29er frames. Unlike, say, supply side economics, this is a theory that might actually hold up.

I didn't initially intend to try this on my KM. I originally had picked up a brand new Soma B side for the very low price of $238 from ebay seller xtremebikeandsport. They sent me a tracking number, and while I was waiting for my shipment, I ordered up some 650B wheels and B+ tires to go with them. A week later, xtremebikeandsport cancelled my order and tried to get me to say I'd refused the shipment. To quote our president elect, dishonest!

Anyway, with wheels and tires around, might as well mount them up on the Monkey. The first part of the theory of B+ holds up, in that they did indeed fit:

Of course, part of the reason they fit is that both tires are laughably undersized. Panaracer jokingly calls this Fat B Nimble a 3.5" tire, but on my Blunt 35 rim, it really measures only 2.65" at the casing:

Even if it were closer to the normal 3" plus tire benchmark, I knew it would fit in my fork no problem. I've run a true 3" tire in there, so this sorta plus tire was no problem:

At the rear, I had the also notoriously undersized WTB Trail Blazer:

It's actually much closer than the FBN, measuring 2.5" actual compared to a 2.8" listed width. I have room for plenty more at the seat stays:

But not a whole lot of room at the chainstays:

Anyway, the idea wasn't just to be fatter--my old setup of a 3" tire on the front and a 2.4" tire on the rear was about as big--but to make the bike handle a bit quicker. After riding 29+ for most of the last year, I appreciated the comfort and traction, but I was growing a bit disenchanted at the inertia of the front wheel. As you steer the bike around corners, there's a bit of lag and extra muscle required to pull the front wheel around. It's not terrible, but on our relatively tight trails, I was curious if I could make it better.

As you can probably infer, my first ride a bit snowy. It's hard to get a good feel for bike handling on the snow. I have to moderate all my inputs so I don't slide out. Because of this, I can't say for sure how this experiment is going so far. I liked the handling, but I need some better trails to get a better feeling for it. I did notice the slightly lower bottom bracket of the smaller wheels. They dropped the bottom bracket about 1/4", giving me a pedal strike on a section of trail where that is normally no issue.

I have an idea how to solve the bottom bracket height--this involves a Niner SIR9 frame with an EBB. But this might work out to be a very nice package: XCish, quick handling, yet still comfortable and capable. Stay tuned.