I decided to see what all the fuss was about, so I built myself a set of 650b wheels and fitted them to my standard 26″ wheeled Mojo.

Similar setup as before, King hubs, Stans Rims, but with different tyres, as I was trying to keep the cost down and these were available.

So, first impressions…the 2.3 front isn’t much different in diameter to a 2.1 SB8 on a 29er, the 2.0 rear is clearly smaller. Clearance on both is….tight – see pictures, but no rubbing so far, even under very hard riding. Running the same shock pressures as before, I’ve not managed to make the wheels contact the frame or fork crown, though I’d wager that my poor jumping skills got me within a nuts cuff on the rear.

I’ve released all the air from the suspension and when compressed, the last 3.5mm on the rear shock is still visible when the wheel kisses the frame, on the front, it’s closer to 5mm of stanchion showing, before the wheel touches the crown.

Riding experience? well, i’ve not done too much so far, but the increase bottom bracket clearance is a benefit, and it does feel more stable at speed, but I can easily feel the extra mass in the wheels.

But in all honesty, I’m really trying hard to feel ANY difference and it may all be in my head.

Pics:

Ojom off here did it too. Worked fine. Didn’t like it.

This is very interesting in an exact 26er to 650b comparison kind of way.
Can’t think of a better way to decide if it’s really all hype or not.

Surprised it feels more stable considering you’ve raised the BB on an already tall bike. Maybe just the weight of the wheels?

I considered doing this on my Mojo HD but some online research suggested that the diameter of my rubber queen 2.2s on flow exs had exactly the same diameter as some schwalbe RRs on crests. So surely the feel of racing ralphs over rubber queens is going to make a much more significant different to the feel of the bike vs the 650b wheels? Can anyone confirm this?

Can’t think of a better way to decide if it’s really all hype or not.

Id by trying a bike designed for 650B wheels against one designed for 26″

As al says different geo for 650b specific frame so not a fair comparison, the remedy I’ve been messing about with I. 29er/ 650 & 650/650 spec has had the angles and shock length adjusted to match the wheels

cynic-al – Member

Id by trying a bike designed for 650B wheels against one designed for 26″

Doesn’t really work though, because then you’re comparing 2 different bikes not just 2 different wheels. Basically there’s no completely fair way to compare the 2. But you can certainly compare the difference in “wheel feel” on the ground, rollover and that, and make some vague conclusions, you just can’t draw any solid conclusions past that. And even that’s knackered by different tyres, pressures etc (because an identical comparison will probably favour one or the other, and as soon as you get away from identical parts it’s all gibberish)

It just strikes me as a little pointless otherwise Mr Wind!

It’s a bit of a funny one, really.

As has been pointed out many times, the difference between 26″ and 27″ is really so small as to be swallowed up by the difference between large and small tyres. So is the geometry really so different betwee 26 and 650B? I doubt it.

Regarding BB height, the Mojo is comparatively low when compared to Canadian Bikes (my history) and so this seems to redress the balance when climbing.

The front wheel is now mahoosive (2.3 650B), like i said, it’s only a shade under my 29er wheels!

Looks good! I did similar with a Cove Stiffee and loved the ride – clearance was very tight at the back so I filed the chainstay bridge down a tad (I’d heard of folks completely removing the bridge but didn’t want to get that radical) – I ran short 650b forks up front so no problems there and running 100mm forks on a frame designed for 130s probably negated any rise in BB height. Don’t want to put a damper on things but I’d be a bit concerned about something getting lodged between tyre and fork brace though and chucking me over the front (not a lot of clearance there).