DURATEC snow bikes have a long tradition. In 2007 Jan Kopka won the Iditarod Trail Invitational, the world's toughest race, where competitors have to cover almost two thousand kilometres through the Alaskan wilderness, on a DURATEC snow bike. All the extreme tests were conducted under arctic conditions north of the Arctic Circle, and the bike passed with flying colours!
Fat Jack is an aluminium frame made of 7020T6 alloy. We offer it with 4.8" width tyres and gearing 1x12 speed in the standard version. It is no easy matter to build a frame for such a wide wheel, and it differs greatly from the regular design. We also have to accept the technical possibilities of the available components and adapt this frame to them. This applies in particular to components such as cranks, rims, tyres, hubs and their width, including fixing system. Upon request the frame can be manufactured with weld-ons serving for attaching carriers. The frame is prepared for rear disk brakes with Post Mount fitting and Syntace X12 Thru Axle. The entire bike is distinguished by very good handling, which the wide tyres also contribute to. These ensure stability on snow covered or icy surfaces. The bike handles deep snow excellently, and is also great for year-round use in the terrain and sand.
The head tube of the frame is conical, version for fork steerer 1-1/8" - 1-1/2". The larger diameter of the bearing in the lower part of the head ensures optimal distribution of the flexural moment from the braking force at the fixed point (i.e., at the level of the top surface of the fork crown).
At the same time as the frame, DURATEC front rigid forks for extreme conditions were developed for this model. The forks have aluminium legs and a post with dimension 1-1/8" - 1-1/2" and brake fastening Post Mount Thru Axle (150 mm wide). We adopt an individual approach to the solution for fixing carriers and bags, because each competitor has his tried and tested products, which can be of differing dimensions.
The model Fat Jack has a 100 mm wide bottom bracket because of the rear construction for wide tyres. The bike is ready for a gearing 1x12 sp. The frame has no fixture for the fitting of a front derailleur, and the rear derailleur cable and brake hose is integrated into the frame top tube.