A regular occurrence through 2025’s trade shows, and now being ridden on the elite cross-country circuit, 32-inch wheels are here, much to the distaste of the general mountain biking population. While I reckon that the average Joe won’t need them, I’m certain that they’re going to find their place somewhere in the sport.

• Gravel is better without tech
• Riding bikes – what’s it all about?
• Electric mountain bikes are getting too powerful

Brace yourselves, it’s happening again! The fieriest argument in mountain biking - and arguably cycling in general - is making a comeback... the wheel size debate. While I love a bit of techy conflict, I got rather comfortable in that people quietened their quarrels over how big a wheel you should be riding, although I’m sure someone would love to tell me that my adoration for 29in hoops is wrong.

One thing’s for sure: 32-inch wheels are coming. But with the wheel size debate settling, the move is one that’s certainly raising questions. Despite the fact I’ve not ridden them yet (although I would love to), I reckon I can foresee how the new wheel size journey will go, and it’s going to be a similar story to 29’s. However, brands will likely have learned from the mistakes of 29in wheels, so the bikes shouldn’t be utter arse. 

We can expect the usual headlines found upon the adoption of 29in hoops, too. 32in wheels will provide better roll over, they’ll gather momentum better and provide a larger contact patch with the ground, so I predict they’ll reward with more traction. On the other hand, they’ll be slower to accelerate due to an increase in rotational mass, and they’ll be tougher to corner, both thanks to that rotational mass and the increased chain stay lengths that’ll be needed to accommodate the wheel (though long chain stays are all the rage at the moment). 

I’ve already written a version of this column once before, but with a firm angle that although wheel sizes have become more of a rider preference rather than dictated by rider height, 32in wheels may best work for very tall riders. That’s the stance that Dirty Sixer’s David Folch takes anyway. While that may still be true, BMC’s unveiling of its 32in-wheeled prototype at the Andorra leg of the XC World Cup just last weekend brought me back to the keyboard. 

2025 32 in proto.jpg, by Liam Mercer

That BMC proto gives us a better look at what we can expect from the big wheel. Ridden by Titouan Carod, it’s rumoured that it’s a medium frame size, which dispels any assumption that 32in hoops will be reserved for taller riders. This also falls in line with the 32in wheel bike we saw at Maxxis’s Eurobike stand, which wasn’t too large. Perhaps most interestingly, the BMC wasn’t actually raced at the Andorra World Cup. However, it was ridden during practice sessions to help the brand gather data on the bike, to find out whether the large wheels bring advantages. So, while the brand predicts an advantage enough to experiment with the wheel size, it’s not yet confident enough to race it. Whether that’s a marketing move or to protect the team’s standings, the UCI permits ‘technical innovation’ in all mountain bike racing, so there’s no reason why the brand couldn’t race the bike.

If we were to take BMC’s prototype as an example, we can expect at least early 32in bikes to bring some compromises in frame design. There’s no space in the front triangle for a water bottle in a bid to keep the standover low while providing clearance for the front wheel, and, to keep the front end low, Carod’s bar was mounted via the most unusual over-under stem. There’s not all that much suspension travel either, to ensure plenty of rear wheel clearance, so suspension travel is limited, meaning we won’t likely see any enduro 32in bikes, for example, committing wagon wheels to XC, just think of the bum buzz… However, DirtySixer’s 32in hardtail gets 140mm suspension up front, but those are much larger frames for much taller people, so there’s more space for more travel.

But I’ll get to the point: do we need 32in wheels? No. Mountain bike wheel sizing has come a long way since the days of 26in wheels being the standard, now with 29in and mullet bikes paving the way for even more innovation. Out of all of the wheel sizes we see in mountain biking, those two configurations are the bigger players, and I don’t see them going anywhere. While bigger wheels may bring benefits to taller riders and XC pros, I don’t believe that they’re going to dominate most of the facets of the sport like 29in wheels have. 

Rather, they’ll go the way of 26 and 24in wheels in dirt jump. 32-inch wheels will be a more specialist wheel size. There has already been a serious investment in the wheel size, from Maxxis and numerous wheel brands, and if it were deemed to pose an advantage to cross-country racing, we’ll definitely see them become more common.

However, I don’t believe that they’ll take over the world. Already, people are kicking off about another standard being a thing, and I don’t think that 32in wheels will bring much of an advantage to the average rider. Rather, my guess is that if they were to become popular, they’ll stick to the cross-country circuit, where clearance issues of such big wheels don’t pose that much of a limitation, as generally, XC riders aren’t using all that much suspension anyway (though some are riding 120mm on certain courses), so the bikes don’t need tonnes of clearance. 

32in wheels are certainly coming; they’ve been in the pipeline for years already, but my point is that while they’re establishing themselves, they’re not going to replace anything. 650b, 29in and 26in wheels, to a point, won’t be going anywhere.

You might also like:

• Is gravel racing an old man’s sport?
• E-MTBs might be getting lighter, but they're still too heavy
• Gravel suspension will make you faster