Sure, it has been tried a number of times before, but up until recently, the concept of using a larger-diameter front wheel has failed to capture the imaginations of rank and file riders. Two relatively modern trends, however, have paved the way for a new look at the concept. One is the acceptance of tubeless tires, which eliminates the need for riders to carry duplicate diameter tubes, and the other is the advent of the 27.5-inch wheel. Founder and designer Brent Foes sums up the latter issue from his own experience:
|If you remember when there were a lot of bike makers making 69ers (26-inch wheels on the rear and 29 up front) they didn't work out all that well. The two diameters were so different that, when the bike was leaned over, the rear wheel would arc so much more than the front wheel, it would screw up the handling. With the 27.5, the two wheels work together and cornering is improved. The rear wheel follows the front and it turns very well - and the bike seems to roll over rough ground like a true 29er.|
Foes Mixer Trail
Enter the Foes Mixer, an all-new chassis from the California builder that is designed specifically to use a 27.5-inch rear and a 29-inch front wheel. Two models will be offered, one with 160-millimeters of travel on both ends for enduro and all mountain riders, and a second with 140 millimeters of travel that will be called the Mixer Trail. The concept is well past the experimental stages, but Foes may tweak the geometry slightly to make room for an upcoming 170-millimeter-travel 29er fork that Brent says will be too good to pass up. The 66-degree head angle is one degree steeper than Foes would use on a 27.5-inch chassis. He says that the larger wheel has so much inherent stability that the bike's steering needed to be a little faster to keep the handling nimble.
Liteville's 601 was redesigned to feature asymmetric wheel diameters (with a 26-inch rear and a 27.5-inch front wheel), and after putting almost six months of trail time on the bike, we can say that Foes is on the right track. Read the review for the in-depth story
. The short version is that the 601 ripped corners at any speed and over any surface... and its smaller rear wheel did not reveal any significant disadvantages in the rough stuff. The key factor seems to be that a slightly smaller rear wheel encourages the bike to track a tighter line around corners. And, putting a larger wheel on the business end of the bike seems to take care of the lion's share of trail chatter, which may negate the need for big wheels on both ends of the chassis.
There is no doubt that the asymmetric wheel concept works, but only time will tell us if and when the trend will catch on within the greater mountain bike community. Brent tells us that his team riders are sold on the concept. Reportedly, it's all they want to ride, and they have already scored some impressive victories at national-level enduro and DH races. I'll be picking up a test bike this month, so expect a full Pinkbike review shortly.