The Xtreme Fat Tire bike frame with its newly designed wheel system, we have now resolved and patented (#61/962,906) the balance of the issues with Fat Tire Bicycle.
Most manufacturers of Fat Tire Bikes took a standard bicycle design and tried to adapt it to fit a Large Tire and Rims. This system does not work for many reasons:
As you widen the BB and Crank Arm distance to get wider wheels, you impact the riders Q Factor and therefore his efficiency and ability to adequately cross train between different types of bicycles.
The Fat Tire Industry’s Bike Design forces them to continue to widen the BB width as the wheels and tires get bigger. By taking the Chain Stay or Bottom Rear Fork out of the equation, as shown, the whole system is out of a 220 mm rotation around the BB.
This system allows my current Wheel / Tire System to work more efficiently with no future extensions on the BB. It also allows all existing Fat Tire BB / Crank Systems to work on this frame. In addition, this system will allow an even wider tire up to 6”+. Plus, it also works with our newly designed 29er wheel system.
This patented system can also be used to create a Full Suspension Fat Tire Bicycle. This system creates less rotational mass, better rotational speed, and maximizes the bike and the bike rider’s co-existence with high efficiency, with out affecting their cross training between different types of bikes: (Road, Trail, Mountain, and Time Trial).
We have completely changed what every other fat tire bike manufacturer is doing. Others fat tire wheel set designs allow the tires width to dictate the tires height, where current tires are approximately 110 to 120 mm wide and 100 mm+ in height.
This causes two issues:
First, it causes extra weight is the tire giving you additional mass to rotate.
Second, it gives you a large tire tread radius which forces you to deflate the tire to get a maximum foot print for soft terrain like sand, mud and snow, and is not as stable of a foot print for downhill racing.
By shortening the tire side walls it changes the tread radius and gives you the same foot print other tires achieve by deflating the tire. This tire gets fully inflated and now you have much less, 2” less, of side wall on each side, better rotational mass, and a much larger foot print, and a tire which is much has more stability. We have not only redesigned the 26" wheel system to make it almost 2 lbs lighter then any other system available, but we have also designed are 29er rim and wheel system creating the lightest system with the largest circumference.
By taking the 29ers' concept, and making the rims 25.2” OD Diameter, you have the same OD of the whole tire system as the existing tires have, (even about ½” more), and much less mass. The results achieving is the same distance traveled, (if not more) per rotation as the tire is ¼” to ½” taller. The last issue is that all the currently designed holed/lighter rims are not symmetrical , they all have holes missing on the top and bottom on these rims, this will cause issues with rotation as speeds are increased , like downhill racing . We have taken that issue and resolved that as well. These changes solve the issues faced with the Fat Tire Wheel System. This design is patented by our company and now has acheived world record status.
PLUS, Surly's new Knard 29er tire fits on our patented rims to create a wheel system that is lighter than any 100mm 26" Tire on the Market!