I started cycling regularly when I moved to Portland three years ago and, for most of that time, I rode around on 700c wheels. But, I outfitted myself with my ideal wheel size about six months ago: the lesser-used 650b.
The most popular wheel sizes of current bikes are 700c and 26″, with 650b being the goldilocks-size in between. The problem I had with 700c was that I couldn’t fit a comfy enough tire on because of clearance issues, everything felt too thin and not quite anchored on the asphalt enough. Additionally, I am on the shorter end of the human spectrum (5’2″), so riding on 700c’s almost made me feel like I was riding a tall bike. I wanted to be closer to the ground and able to make sharper, cushier turns, but I didn’t want to go with 26″ wheels because the frame I chose was so small (46cm). I needed something versatile that would be great for city riding, trail riding, and touring, which is exactly what this wheel size provides.
Up where I live in SW Portland, there is an abundance of unimproved roads. Additionally, I love riding through Forest Park and other trails around Portland, and 700×23 tires just weren’t making the cut anymore. I found the experience jarring and unpleasant, which is why I’ve switched over to something a little more generous.
In terms of specs, what I’m riding these days are Velocity Blunt SL 650b rims and Compass Bicycles Babyshoe Pass 650x42mm tires, both of which are absolutely superb. The size of these rims gets me just slightly lower to the ground, making my ride a little more aggressive, which is hard to obtain as a person that is below average height. Cycling is dominated by white males of seemingly average man-height, which means that everything is designed for their comfort. Thus, I had to essentially design and put together a bike that would actually fit me (with the help of my partner, who is a certifiable bike nerd even more so than myself). If you’re 5’5″ or above, perhaps you don’t have to go out of your way to be slightly lower to the ground. However, I will say that the sharper turns that 650b allows in addition to the ability to avoiding hitting your foot when you move your fork are aspects that would appeal to people of all heights.
I’ve noticed a lot of bicyclists saying that 650b doesn’t feel as stable or as easy to climb with as 700c, and I really have to disagree. I wonder if this has anything to do with difference in height, though. I feel nice and anchored to the ground, I don’t feel like I’m going to tip over, and I actually feel very nimble and deft operating with this wheel size. I glide over every bump with ease as the slightly wider tires absorb a good amount of shock. In addition, there has been no difference in my average speed, both climbing and descending.
Perhaps the one downside to 650b is that it’s not the most readily available tube or tire size. Not every bike shop will have sizing to accommodate 650b. I’m always sure to carry an extra tube with me just in case a shop nearby doesn’t have one that will fit. However, with the high-quality, cushy Babyshoe Pass tires I’m unlikely to get flats in the first place. I have yet to have one with this wheel and tire combo (knock on wood).
The reason I switched over to this wheel size is because I was building up a bicycle from scratch and I wanted it to fit me extremely well. Despite it being occasionally high-maintenance, this wheel size has proven to be my ideal and you couldn’t pay me to switch back to 700c. They’re really the happy-medium wheel size for smaller riders and riders looking for a more comfortable and nimble experience.