What does “wide” mean for gravel rims now? And does it matter?

Earlier today, Vancouver Island’s NOBL Wheels released one of the widest gravel-specific rims currently available to the public. Not quite the widest, but pretty wide. Which made us think, what exactly counts as a wide rim for gravel now?

This isn’t just about rims, of course. The need for wider rims is a direct result of racers (and now more and more rider) running wider tires. Significantly wider tires. Wide enough that racers can borrow rubber from their sponsors mountain bike catalogue instead of waiting for brands to release a wide-enough gravel-specific tire.

That has left rim producers playing catch-up. While an XC race tire can, in a pinch, double as a gravel tire, racers have more specific demands for their wheels. Rims have to be light like an XC wheel. But, for these three to eight hour endurance events, racers also want them to be quite aerodynamic. Aerodynamics are something that’s never really been a consideration for mountain biking. So brands have to come up with an entirely new rim to properly fit these 2.0″-2.2″ tires that riders are racing.

There are a few good reasons why wider tires need wider rims. We’ll get into those a bit below.

So, what is wide? What was wide?

As mentioned, NOBL’s new wheel is wide, but not the widest commercially available rim. That honour goes to Zipp. But there’s relatively few options out there that are willing to push beyond the old standard for “wide” that sat at around 25mm for years.

Zipp, a SRAM-owned brand, released the 303 XPLR S with a girthy 32-mm internal width. At 32mm, that’s the widest rim you can buy by a big margin. 32mm is, to be clear, wider than most cross country mountain bike race wheels currently on the market. Going that wide comes with some drawbacks, along with the aerodynamic advantages Zipp claims to achieve. Specifically, SRAM/Zipp say the ultra-wide rims are only officially compatible with a limited range of tires. That range is growing, but it still means limited options.

Then there’s Faction Bike Studio. The Quebec-based design house created a prototype gravel rim that dwarfs Zipp’s big boys in almost every measurement. The Faction/Dangerholm wheels are a staggering 42mm internal, ballooning out to 52mm external width at their widest point and a futuristic-looking ridged 54mm rim depth that looks kind of like an…