It wasn’t all that long ago that 29″ wheels and tires were considered huge. Then a few builders including DirtySixer created a 36er. Less of a gimmick and more of a sizing tool for the very, very tall, DirtySixer has been steadily selling 36″ bikes to clients around the world. But if you’re talking in percentages of the population, very few would qualify to play professional basketball, or ride one of DirtySixer’s 36″ bikes.
That doesn’t mean that 29″ is the next best size. At least, not according to David Folch the founder of DirtySixer. Citing the gap in wheel size between 29 and 36″, David stumbled across a new size. Well, technically one that was already out on the market – but really only as a cheap 32″ cruiser from a big box store…
Originally introduced on a cruiser line from Kent, 32″ tires have technically been around for a while though David says the cruiser tires measure more like 31.5″ for the outer diameter. The important thing here was that the BSD (Bead Seat Diameter) was established at 686. Compare that to 622 for 29ers and 787 for the 36ers and it gives you an idea of the relative size difference.
The key to DirtySixer getting into the 32″ wheel game came when one of their suppliers decided to make their own rim and tire that would fit. That meant a 2.25″ tire that actually measures 32″ for the outer diameter, and a burly 42mm wide aluminum rim that uses the same extrusion as another wheel from the same company. Drilled with 36 holes, the wheels should be plenty durable and will run the DirtySixer tire that should have a good all purpose tread pattern.
After getting a hold of the prototype wheel and tires, David went out to the titanium frame building school at UBI (United Bicycle Institute) to create the first 32″ prototype frame. Like their 36″ DirtySixer, the production bikes will be hand fabricated by Ventana Cycles in California and will feature an aluminum frame with a chromoly fork.
Sizing will be available in three option with the Small starting out for riders 5’8″-6′, Medium for 6’1″-6’4″, and Large for 6’5″-6’8″. David mentions that these sizes aren’t set in stone and that there will be some overlap between the 36″ bikes, but that’s the rough plan. Given DirtySixer’s diminutive size (as a company), they are taking to Kickstarter to launch the first run of bikes which will be offered in All Road builds (flat bar, rigid fork) and maybe a road build with drop bars as well. A mountain version may follow when actual 32″ mountain bike tires are created.
Frames will have the option for 17 different powdercoat colors, single speed, 1×11, or Rohloff drivetrains, and many other options to customize the ride and the fit. At 6’6″, David is shown putting the prototype through some test runs above. Keep an eye out for their Kickstarter on the link below.