Another 650B Tire

The Bubblegum Princess with the new Venture tires from WTB.

The subject of tires for any bicycle generally engenders a fair amount of discussion amongst cyclists. To be honest, a lot of the banter is pretty ridiculous. There are a lot of old, not very sensible beliefs about how tires work, what sizes are "best", what tread patterns work, and which tire pressures are best. (Max pressure!)

The thing is, many of these entrenched opinions were never tested by their adherents. They were just adopted out of necessity, convenience, or trust in a "knowledgeable friend". Sometimes all three at once. That isn't a good thing, and you should strive to think for yourself. That requires effort, time, and patience. Things in short supply in the "Age Of Information". People are just too darn busy to deal with that, so they just hear something and roll with it. When they are presented with opposing facts, they fall back on the source of their knowledge, or they just get angry because now you've shown them something and they might have to think about it. Oh! The horror! 

All that to say that I have an opinion on the whole 650B gravel wheel/tire thing and that I have ridden this format enough now with enough tires that I feel pretty confident in what I think about it for my purposes. Typically, if I wasn't running tires for testing, I wouldn't be on 650B very often. There are times I feel, again for myself, that it gives an advantage. That would be for softer, wetter conditions.

Then it gives me more float and stability. It doesn't do the "pizza cutter" thing and it makes riding in poor conditions easier. That's when I see an advantage over my "normal" 700c X 43-ish millimeter tires. But when it comes to drier conditions, it isn't an advantage. It isn't bad, but it isn't an advantage to run them.

More tire testing here. 700c Donnelly EMP in this case.

 One of the things a lot of folks don't think about when they swap out to 650B wheels is how the smaller diameter changes a few things. Maybe you already realize that the bottom bracket gets closer to the ground, which can cause pedal strikes at times. But that isn't all smaller wheels do.

They also change the handling of your bike. due to the idiosyncrasies of front end geometry, smaller diameter wheels make your bike less stable. Probably not something you may have thought about. Then too, smaller wheels also affect your gear ratios. Your big ring gets "less big ring" with smaller wheels. Your granny gear gets "more granny" too. If you have  a 1X rig, this is even more important to consider.

So, why bother with 650B wheels at all? That's a really, really good question. 

Part of the hoopla is industry driven. Someone creates a new platform, or, in truth, puts a new coat of paint on an old idea, and the marketing guys go to town on it. The hope being that "it" motivates you to part with your dollars. That's how the ball keeps rolling. It's what we do, so I understand that as well. Sometimes those ideas are goofy. Sometimes they are not.

In this case it was kind of a patch to get wider tires in a road-ish frame. It's not a new idea, (see above paragraph), but in these days of "plus all the tires" it was a way to slam in some 48mm tires with a road crank/cx style format. Then some bike packing folks got a hold of the idea and started tweaking out clearances, using 1X drive trains, and squeezing in 2.1'-2.2" 650B mtb tires. Some are even doing mtb drive trains and slamming in 3" 27.5+ tires and wheels.

This then begs the question- "Why not just do a 29"er drop bar mtb?" Another great question there. Of course, many of you are already saying "Fargo" as you read this. It would seem that the industry and times have come right back around after 10 years to where the Fargo has always been. A great example of which is the Mason Cycles "In Search Of". The Breezer Bikes RADAR Expert I recently had in for review is another good example.

My Fargo, December 2008. A bike way ahead of its time.

So going back to these new 650B tires coming out in the 47mm-50mm sizes. Well, I like to think of them as a stepping stone toward what I feel is already coming around again. More "Fargo-ish" bikes that can handle big 29"er tires and wheels but could also run a 45mm tire with ease.

The benefits of swapping wheel sizes works if you are limited with sticking to a road drive train, because frame clearances are limited to be able to run those cranksets. Yes, 1X gains you a bit of breathing room, but I believe this is also a stop-gap until something that should have happened a long, long time ago finally does happen. That being when road based drive train dimensions change.

Call it "Road Boost", or just "Neu-Road", or some other fancy marketing term, but road over lock dimensions for hubs and bottom bracket widths are going to get wider. When that happens, then the 29"er with a road based crank set and capabilities to run 2.4" tires easily will be all over the place. 650B will fall to the wayside as the "fat tire" option for gravel/back road/bike packing. Big wheels just roll over stuff better and that's a fact. Give those hoops some flotation capabilities over the current 43-ish millimeter widths we are stuck with now, marry that to a wide ratio road double, and then you'll have the bike of the future for the gravel/back road/bike packing riders wanting a wider tire than 45mm. 

But, as always, don't take my word for it. Think it over for yourself. I'm probably completely bonkers.