Why 650b wheels

The staff here at Glory Cycles have put both the c and B wheels to the test and the definitive answer is Maybe that wasn't the easy answer you wanted. But scroll down for the benefits and drawbacks of each, where each size excels, and decide which is best for you.

Because at Glory, we believe that each bike should reflect the needs and wants of the person riding it. The B wheel allows for a larger tire which in turn gives a more comfortable, cushioned ride. The wider tire also allows riders to use lower tire pressure, increasing the handling of the bike off road.

While it's capable on the asphalt, the B really shines in serious off road situations like tight mountain bike trails and rough sections of gravel adventure rides or races. In a nutshell, the B gives the bike a mountain bike feel. The answer is yes but not as much as you might think. That means the bike will sit 19 mm. However, you will probably run larger tires when you switch to b. The geometry remains more or less the same because the larger tires make up for most of the difference in wheel size.

In other words, a c rim with a skinny road tire and a b wheel with a big off-road tire has around the same total diameter including the tire. More specifically, many riders find that b wheels fitted with mm wide tires measure about the same in diameter as c wheels fitted with mm wide tires.

Of course, in practice there is usually a slight difference in total diameter. For example, c x 40 mm tire measure about 2 cm. Because the total diameter including the tire stays about the same, the bottom bracket height, frame geometry, and gearing also stay about the same. With proper tire selection, there are very few issues, compatibility wise. Both b and c are great wheel size choices for gravel bikes, mountain bikes, road bikes, and touring bikes.

In this section, I list all of the pros and cons of each wheel size to help you make an informed decision. Most c or 29er gravel, touring, and mountain bikes can be converted to b without any issues. In fact, some manufacturers, like Salsa and Kona, even advertise this option on their marketing material. They design some of their frames to be dual wheel size capable. The problem is that not all frames offer this flexibility. When compared to a b x 47mm wide tire, there will be a slight difference in diameter.

It turns out that the difference will be around 1 inch 2. Most riders will feel the difference but will get used to it in after riding a few miles. The problem is that, even though the difference is minimal, there are a few compatibility issues you can run into.

Because the rim radius of b wheels is 19 mm smaller than c wheels, the brakes have to reach that much further to grip the rims. This means you will need to replace your rim brake calipers with a pair with a longer reach. To help you measure brake reach, check out this guide from Sheldon Brown. Usually, u-brakes and centerpull calipers have long enough reach. Another issue you may encounter when converting from c to b the bottom bracket being too low.

Candidate for B Wheels? Your thoughts? Mike G- Typically bottom bracket drops are not very deep. I would think you would be okay, but I cannot say with any certainty. I would be very surprised to find out that the Torker model you specify has a deeper drop than 75mm. If you are going to carry a front load you want low trail.

Not twitchy. On any surface. If I converted I can run a x44c tire and still get better mud clearance. Kris- Wow, you are asking me to make a call on a bike I cannot see. That is nigh unto impossible to do with any good outcome. So, I would ask kindly that you consult a bike shop, or a local frame builder if possible, where you can take the bike and get some good feedback based upon some real world observations of your specific bike.

That said, since you are thinking of an upgrade, why not press that into go mode now instead of waiting? This entire quandary could maybe be avoided? Sounds like your best option from what I have here to work with.

Thanks for the reply. What I will say is after running my 32c tires again I feel like converting to a b would make sense for me if I can achieve the nimble-ness that my narrower tires have but gain the volume and traction that I get with my 40c tires.

Lots of room, Ryan. What do you think is the biggest B tire that would fit in the Tamland ? This is a Bay Area bike that will not very often see muddy conditions, but lots of packed and loose over hard. Ryan- Ironically it was a Tamland that I saw at this past Dirty Kanza that had the B wheel set up and swept back touring bars that I was reminded of when I read your comment.

Good luck with the project and I hope you have many miles of smiles on board that rig. Maybe less than a half a millimeter of clearance! So, obviously I never rode that set up. For B? I would think a lot of this depends upon the rim that you use and specifically the inner rim width.

Keep in mind that frame clearances are also for other debris besides mud. Great article. Now we are searching how to find thise wheels in France to do some gravelbike adventure. Thanks for great article. You may have made a typo in your conversion from inches to cm. That is better news for those like me who are looking at b to increase standover height. I turned my dbr axis titanium bike into a b wheeled gravel bike, mounting Schwalbe g one 1.

I foynd the assembly definitely too stiff and twitchy. Things got better with Vee Tires 1. Overall, I agree with you, compared toy old bike, a Rotchey Swisscross with 40mm tyres, the DBR is more nervous, has less momentuum but is more comfortable with its 1. If you have a 16 bike to recycle, going b is a good choice. I am torn between the Niner RLT 9 steel vs. I understand the steel would provide more comfort while the alum.

But then I keep thinking what if you put a b wheelset with Horizon 47mm tires on the aluminum, then would you have more comfort comparable to the steel version but still keeping the better speed profile? What are your thoughts? Andrew Warfield- Comfort gains would be marginal depending upon several factors.

Potentially- yes- it could be noticeably better. However; you could also make similar or even better gains in comfort by simply swapping to a more compliant seat post, as an example. One useful feature of gravel bikes with big tire clearance is the opportunity to use both c and B wheels with the same frame.

Each of these wheel sizes offers different benefits and ride experiences suited for various adventures. Shimano GRX gravel wheels are available in both c and B sizes, delivering reliable performance for diverse riding conditions. With a larger overall circumference, c wheels often roll faster on hardpack and non-technical surfaces due to lower rolling resistance.