Bicycles were never permitted in the National Wilderness Preservation System by the 1964 Wilderness Act or any subsequent designation legislation. It’s understandable, however, why there is some confusion on the issue.
On March 9, 1982, the Forest Service — under pressure from the nascent mountain bike community, I suspect — sent direction to wilderness managers to suspend the enforcement of the federal rule — 36 CFR 261.16(b) — which prohibits "possessing or using a hang glider or bicycle" in wilderness areas. "During the last CFR revisions we intended to remove ‘or bicycle’ but the change did not get effected," wrote Associate Deputy Chief J. B. Hilmon.
The "or bicycle" language was never removed, however. On the 17th of February, 1984, Hilmon again wrote to Wilderness Managers: "After careful examination of the Wilderness Act and its legislative history, we are certain that Congress intended that bicycles be excluded from wilderness.
"Section 4(c) of the Wilderness Act, (Public Law 88-577), states, ‘There shall be no temporary road, no use of motor vehicles, motorized equipment or motorboats, no landing of aircraft, no other form of mechanical transport, and no structure or installation within any such area.’ … The legislative history of the Act indicates Congress intended that travel within these special areas be by primitive means, i.e., foot, horse, or canoe, except when otherwise permitted by specific legislation. Based on the law, bicycles have always been prohibited in National Forest Wilderness units."
Hopefully, this will end this particular bit of mythology on the part of my mountain-biking buddies.
Fort Collins, Colorado