Modernize your outdated 15mm thru-axle bike with Forkmods

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It’s an all-too-common scenario in the era of rapidly changing bike “standards”: Adrian Hodgson was recently looking to replace the wheels on his 2016 Trek Domane 6.9 Disc, but he had few good options. Despite the bike only being a handful of years old, the 15 mm-diameter thru-axle format used on the existing fork and front wheel had already been replaced by the now-dominant 12 mm one, and most wheels were already only being offered in the latter size.

“All of the wheels I looked at were fine if you had 12 mm but the choice was very limited if you had a 15 mm fork,” he said. “I Googled for hours on a number of occasions and even made contact with Trek and DT Swiss, who made the bike and standard hub components in the first place, but neither they nor anybody else could sell me something. My choices were either, buy a lower-spec wheel (which I did), or buy a new bike with a 12 mm fork.”

Hodgson ended up purchasing a new wheelset from Australian brand Caden, and company owner Ben Cawood graciously included both 15 mm and 12 mm endcaps with Hodgson’s order, but the issue still left him unsettled.

Hodgson continued to search, and eventually found a generic thru-axle conversion kit that was basically little more than an aluminum sleeve with a 15 mm outer diameter and 12 mm inner one. That addressed the hub part of the equation since most 15 mm end caps use the same outer diameter as 12 mm ones, and thus fit just as well in the dropouts. However, many forks also have proprietary parts that still only work with the original 15 mm setup.

Offering thru-axles and reducer sleeves is straightforward enough, but adapting the threaded ends of a thru-axle fork is more involved.

Hodgson continued to chat with the person behind that sleeve, and ultimately they developed a conversion kit specifically for that generation of Domane Disc.

“People liked the generic kit, and now the Domane kit, and more started asking for a kit to suit their bike/fork combo. It quickly became clear that there was a demand for this type of solution, and was created.”

Just weeks after being launched, Forkmods now offers nearly a dozen different conversion kits for various bike and fork brands, such as Specialized, Trek, Focus, Fox, 3T, and several others. Additional kits are already in the works, too. Each kit includes replacement threaded ends for one side of the fork, a flanged reducer sleeve for the other side, and a tooled aluminum 12 mm thru-axle.

Forkmods offers nearly a dozen different conversion kits already, with more to come.

Not surprisingly, Forkmods isn’t officially endorsed by any compatible brands, and there’s currently no direct collaboration to help develop the kits.

“Customers have played a big part in new product development through providing bikes, forks, measurements, and patience while new parts are made and tested. It’s a cool little community of people who want to upgrade their bike to be able to use whatever wheels they like or swap them between other 12 mm bikes they have.”

Retail price for each kit is AU$120, and although pricing on the Forkmods site is currently only listed in Australian dollars, the company does ship worldwide. Moreover, since kit prices for international buyers are based on current conversion rates, buyers living in countries that are enjoying particularly strong currencies can get the kits for a pretty reasonable sum.

More information can be found at

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