AORE Partner News Summer 2016 - Page 8

By Mark Eller, Communications Director at IMBA

This story originally appeared in Trail News, the print newsletter of the International Mountain Bicycling Association (IMBA). Republished here with permission.

The International Mountain Bicycling Association (IMBA) published its first book on trail design, Trail Solutions: IMBA’s Guide to Building Sweet Singletrack, in 2004 and followed with Managing Mountain Biking: IMBA’s Guide to Providing Great Riding, in 2007. Those books have had a profound influence on trail design and construction, helping thousands of trail builders, bike advocates and land managers learn how to create sustainable trails.

Just as mountain bike technology has continued to evolve, so, too, have trail building techniques. In 2014, IMBA published Bike Parks: IMBA’s Guide to New School Trails, which is already helping create the next generation of bike-specific facilities. The emphasis in Bike Parks, however, is on organizing, funding and overseeing bike park efforts. Unlike IMBA’s first two books, it does not go into great detail about the specific design and construction methods that produce bike-optimized trails. This article is meant to help fill that gap.

Emerging Trail Types

Singletrack With Out-Sloped and In-Sloped Tread: Typically hand built and from 1.5 to 3 feet wide, these trails closely resemble traditional trail construction, but add bike-optimized flavor by out-sloping the dips and in-sloping the crests of grade reversals. Turns can be in-sloped on the flats but may be out-sloped for better drainage when diving into gullies. Side slopes of 40 percent or less are best—steeper slopes require lots of earthworks to build turning platforms. This building style works well for both shared-use and single-use trails, generally with two-way traffic.

Turning Trails Inside Out:

Emerging Trends in Mountain Bike and Multi-Use Trail Design