DMR 20switchinch 2

If you’re still riding 26″ wheels, there is a good chance that you have contemplated going 27.5″ on your next bike. But with all the new tires, and wheels, and tubes, it’s a pretty big commitment. Fortunately, DMR seems to have your back with their new 20SwitchInch rim adapter that allows you to gain all the benefits of 27.5″ on your current 26″ wheels. Of course your frame will need to have enough clearance to run the bigger 27.5″ tires, but if you’re good there you’ll love the 20SwitchInch system.

Switch past the break for more…

DMR 20switchinch

From DMR:

DMR  20SWITCHINCH  (say like “twentysixinch”…get it!)

At DMR we like versatile products that let the rider decide and try out options..

For example:

APS – our adjustable pivot bosses on the Trailstar and Sidekick frames allowed the rider to switch between 24” or 26” wheels. Swopouts – allow the rider to convert their frame between Vertical dropouts 135standard or 142X12mmwith mech hanger or Horizontal for single speed. The latest dilemma for all of us is 26” or 27.5” wheels size.  Can’t decide? Want to try without spending out on a new frame & wheels etc??

What actually is the difference? Turns out its only 12.5mm on radius at the tyre seat! {Tech spec 26” rim bed diameter is 559mm , 650b [27.5”] is 584mm  = 25mm difference in diameter } So we’ve been testing prototypes of a rim bed spacer that fits a bit like a tyre into the 26” rim and increases the diameter to the 650b tyre seat diameter and provides a new rim profile on top. Working name is the DMR 20switchinch and it has a rigid outer rim with the flexible ‘liner’ fitting bed that is mechanically locked to the ‘receiver’ rim & also further clamped by air pressure [actually a significant amount of force is exerted over the area around the circumference.]

Fit the 20switchinch, fit new tyres and tubes and providing your frame and fork has clearance for 27.5 tyres you are good to go. Naturally the system is for Disc brake use only. We’ve been testing on a couple of widths and it will work over a tolerance of 4mm – inner rim width of 19-23mm. The prototype system adds about 200grams per wheel, but we expect to save up to 70 grams on the production version. The floor of the 27.5 rim bed is tubeless ready with the bead hook feature built in. Testing so far has been going well with Olly Wilkins riding DH in Madeira – Below.

DMR 20switchinch 3

Still early days but we are hoping to have it available later this summer for around £27.50 each.

We are also prototyping a 27.5” to 29” and a “narrow to fat bike” version, but we are not convinced on the size of this future market yet.



  1. Wanna make your wheelset heavier? Just add extra rims. And then you can have all the benifits of 26.5, but don’t worry about geometry. Just don’t get any mud on your tires or use all your travel.

  2. do they make an adapter to go from 29 inch to 27.5? i’ve been looking for years and still can’t find one anywhere.

  3. this is nothing, my engineers are currently working on an auto adjusting wheel size wheel. sensors on the bike and in the wheel detect the terrain and an electronic unit automatically resizes the wheel for optimum performance. search “electrosize” in kickstarter to get in on the ground floor

  4. There are way too many morons who bought this hook l,ine and sinker. Similar to the whole 27.5 craze in general.
    I picked my size (26) and will be a dick about it forever.

What do you think?