BikeBiz Bicycle and cycling retail news
Upgrade’s in-house mountain bike label DMR has developed a 26 to 27.5-inch wheel conversion kit, revealing a system it calls "20SwitchInch."
Acknowledging that many mountain bikers are understandably reluctant to fork out on a new bike or components for the sake of 1.5 inches, Damian Mason and team rider Olly Wilkins have co-developed a ‘rim bed spacer’ that should at least save riders the trouble of buying new wheels.
BikeBiz was first given a look at early prototype sections back in January at the CoreBike show. We took the opportunity to find out more during the show, with Mason telling us DMR has always been at the forefront of designing versatile products that can adapt to suit the needs.
"At DMR we like versatile products that let the rider decide and try out options. For example the APS system – our adjustable pivot bosses on the Trailstar and Sidekick frames that allowed the rider to switch between 24” or 26” wheels. Then there’s our Swopouts – allowing the rider to convert their frame between Vertical dropouts 135 standard, or 142X12mm with mech hanger or horizontal for single speed."
The latest dilemma for all of us in the cycling world is 26” or 27.5” wheels size. (We’ll get to 29ers in a minute…)
So, what actually does this product do?
Mason explains: "Turns out it’s 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-inch rim and increases the diameter to the 650b tyre seat diameter and provides a new rim profile on top."
"The 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 and also further clamped by air pressure [actually a significant amount of force is exerted over the area around the circumference, says Mason.]"
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," added test rider Olly Wilkins, who has spent several months trialling the prototypes both at home and in the Madeiran mountains.
"The prototype system adds about 200 grams 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.
Upgrade is hoping to have the conversion kits available later this summer for around £27.50 each.
So, what about 29ers?
"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," concludes Mason.
