R. Cunningham
Gary Fisher Cycles has redeemed a stone the forkmakers have ignored for many years. Fisher’s folks were worried about how to improve the Cake’s slow steering. Keith Bontrager, a respected frame builder, suggested Fisher increase the fork offset. This is the distance the front axle is offset from the steering axis. The fork offset could be increased to reduce the amount of trail? The steering geometry was changed to give Cakes’ front end a lighter and more responsive feel at singletrack speeds. It was named Genesis 2.0 by Fishers Marketing Wing and will be on the?07 HiFi lightweight cross-country suspension bicycles.
Because of the steep geometry of suspension forks, the offset for almost all suspension forks is 4 cm. Problem is, the ideal amount of fork offset can vary with head angles, wheel diameters and changes in speed.
Gary Fishers Fat Possum would welcome Genesis 2 steering. It is extremely stable in straight lines, but very heavy handed in corners. Why? Why? Frame designers and fork makers did not consider trail and fork offset in their calculations. Although the one-offset-fits all standard was an economic saver for fork manufacturers, it can be detrimental to handling, as Gary Fishers’ designers discovered.
The discovery of Fisher is actually a rediscovery. Gary’s very first mountain bikes (remember Ritchey Mountains Bikes) had nearly two inches of offset and slightly lower head angles than modern racing sleds. They also steered wonderfully. Nearly every mountain bike manufacturer of the time copied Gary’s original steering geometry. Keith Bontrager, a cutting-edge designer, discovered that reducing fork offset (which increases trail) provided stability to nervous racers. Paul Turner created Rock Shox and adopted the shorter offset of 4 cm as his standard. All other suspension manufacturers followed Rock Shox’s lead.
Riders are now choosing shorter head angles, fatter tires, and longer-stroke suspension. All of these have a damping effect on bikes’ slow speed steering. It was only a matter time before some hotshot would discover the magic of fork offset, and apply it to a modern trailbike.
Gary Fisher and Keith Bontrager deserve a special thanks for bringing back the old-fashioned aspect of mountain bike handling. Manitou should be commended for having their suspension forks retooled with an additional offset in order to produce the G2 front suspension.
This is the bad thing about G2 (there is always a negative side to innovation). Every big-brand bike manufacturer will claim that they are better at rake, trail, and offset and then order forks with drastically different offset measurements. This ‘new’ technology will likely make mountain bikes even worse for a short time. tuning feature will make it easier to use. And let’s not forget about the mess G2 will make of the aftermarket process and replacement fork process. Here we go again.
