9. APPENDICES Disciplines of Mountain Biking

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1 9. APPENDICES 9.1. Disciplines of Mountain Biking Cross-country Cross-country mountain biking is the oldest discipline within the sport and is analogous to cross-country running or skiing. It involves riding across all types of terrain and slopes. Participants may be seeking thrills, fitness or the opportunity to enjoy nature. Specialised cross-country mountain bikes are light weight, with up to 27 gears and may have front and/or rear suspension. Cross-country trails are similar to walking trails narrow singletrack corridors through the bush, only slightly wider than a set of handlebars, although they can be as wide as a vehicle trail. Trails may be loops or point to point rides. They can be surfaced or unsurfaced and may use materials such as rock and timber for obstacles or armouring. Although cross-country trails generally require a low level of construction, they can be time consuming or expensive to build due to long distances involved or lack of access for machinery and materials. Crosscountry trails probably require the greatest amount of space, although it is possible to create a longer track by increasing the twists and turns of the trail. Downhill Analogous to downhill skiing, downhill mountain biking is a speed oriented sport, where participants start at the top of the hill and ride down. As downhill bikes are not designed for riding up hills, transport is required to get riders and their bikes back to the top of the hill. Downhill bikes have both front and rear suspension, are heavy and generally have fewer gears than cross-country bikes. As downhill often involves high speeds and crashes are more common, participants wear full-face helmets and extensive body armour to protect themselves. Downhill trails are generally more difficult than cross-country trails and may include drop-offs, jumps, narrow bridges, rough terrain and steep gradients. Due to the higher speeds of downhilling and the heavy bikes, downhill trails often require heavy armouring with rock or timber to prevent erosion, which can be expensive. Careful design and close attention to gradients and corners may reduce the amount of armouring required, but won t eliminate it. Downhill trails are by definition point to point trails, require a fairly large amount of space and clearly require a downhill slope, with access top and bottom. 4x A relatively new discipline, 4x is best described as a fusion of downhill mountain biking and the sport of BMX. In competition, four riders compete against each other to be the first to the bottom. 4x bikes are usually small and light, with front suspension only and fewer gears than cross-country bikes. 4x tracks look similar to BMX tracks except they are linear rather than looped and usually slope downhill sightly. They feature large banked corners or berms and jumps in various shapes and combinations. Large amounts of fill are required to construct the jumps and berms. They are usually surfaced with fine gravel or granitic sand and have no rocks, logs or other natural obstacles. A large starting mound with a start gate is required at the beginning of the track. Limited space (approx 1000 sq/m) is required to build a 4x trail, making them suitable for many urban areas. Also, due to their compact nature they are quick (7-14 days) and cost effective to construct. Jump trails or dirt jumps Also borrowing heavily from BMX, jump trails focus on jumps rather than speed or endurance. Users of jump trails tend to be young and consequently many jump trails are located in urban areas. Jump trails are usually entirely constructed from dirt, with large mounded jumps built up above the natural ground surface. The jumps often feature a gap between the take-off and landing points. Jump bikes are heavily built to withstand jumping, usually have front suspension only and may have fewer gears than cross-country bikes. As with 4x tracks, jump trails can be built with limited space (approx 1000 sq/m) and time (7-14 days) making them cost effective to construct. 203

2 Freeride Freeride is probably the newest and least understood discipline of mountain biking. It incorporates elements from all disciplines, but emphasises advanced level mountain biking, creative riding, extreme manoeuvres and high risks. Freeride bikes are similar to downhill bikes heavy and strong with front and rear suspension. Riders also wear body armour and full face helmets. Freeride trails are hard to define but can include natural features like boulders, logs and small cliffs, as well as constructed features made from timber and other materials. Due to its unstructured nature, freeride trails can be almost any sort of trail that requires high levels of skill and risk. With constructed features like timber bridges, see-saws and ramps and the use of jumps and drops, freeride trails don t necessarily require large areas like downhill and crosscountry. 204

3 9.2. IMBA Trail Difficulty Rating System IMBA has published a Trail Difficulty Rating System that can be used to apply a difficulty rating to mountain bike trails. This system uses trail parameters such as width and gradient and the technical features of the trail to determine a difficulty rating. As there is no Australian standard for the classification of mountain bike trails, the IMBA Trail Difficulty Rating System is widely used in Australia. World Trail believes the ratings are well understood by mountain bikers and recommends rating mountain bike trails using this system. IMBA Trail Difficulty Rating System Easiest Easy (white circle) (green circle) Symbol More Difficult (blue square) Very Difficult (black diamond) Extremely Difficult (double black diamond) Trail Width 1800mm 920mm or greater 600mm or greater 300mm or greater 150mm or greater Tread Surface Hardened or surfaced Firm and Stable Mostly stable with some variety Widely variable Widely variable and unpredictable Average Trail Grade Less than 5% 5% or less 10% or less 15% or less 20% or more Maximum Trail Grade Natural Obstacles and Technical Trail Features (TTF) Max 10% 15% 15% or greater 15% or greater 15% or greater None Unavoidable obstacles 50mm tall or less Avoidable obstacles may be present Unavoidable obstacles 200mm tall or less Avoidable obstacles may be present Unavoidable obstacles 380mm tall or less Avoidable obstacles may be present Unavoidable obstacles 380mm tall or greater Avoidable obstacles may be present Unavoidable bridges 920mm or wider Unavoidable bridges 600mm or wider Unavoidable bridges 600mm or wider Unavoidable bridges 600mm or narrower TTF s 50mm high or less, width of deck is greater than half the height May include loose rocks TTF s 100mm high or less, width of deck is less than half the height May include loose rocks TTF s 100mm high or greater, width of deck is unpredictable Short sections may exceed criteria Sections may exceed criteria 205

4 9.3. ABC (Multiple) Lines System The A-B-C lines system has been developed to give riders of varying riding abilities options when riding a specific trail. The system provides options for beginner, intermediate and advanced riders when a challenging section of terrain presents itself on a trail, while limiting any forced accidents that may occur. A forced accident occurs when a difficult section of trail has no options available to the rider, and the rider is forced into a snap decision on how to negotiate a difficult route. The rider may be forced into a position that is beyond their own skill level. With an A-B-C lines system the trail splits into two (2) or three (3) different options with verifying degrees of difficulty designed to cater for all users. By employing A-B-C options on a particular trail users of different abilities can ride together in groups and still have a challenging and enjoyable experience. The ABC lines system is beneficial as it reduces the riders risk if they are not comfortable with a particular section of the trail. A-B-C lines can be implemented on technical areas, rocky outcrops, fallen logs or gully crossings. A-B-C lines need to be signposted effectively to reflect the difficulty rating of the riding line that the user has chosen to negotiate. 206

5 9.4. Site Treatment Sketches 207

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19 9.5. Routine Trail Inspection Reporting Form Route/Trail Name:.. Inspected by: Date:.. Item Inspected Describe Maintenance Required Tools Required Are grade reversal outlets clear of soil and/or organic material? Priority GPS Location Photo Reference # Have any unauthorized trails been created in the immediate vicinity? Is trail surface free of rubbish/sticks/ branches/leaves? Are all technical trail features in good condition? Is the trail surface in good condition? Are there any puddles or muddy sections? Are there any holes in trail surface? Are there any unauthorized modifications to the trail? Is there any evidence of erosion? Are there any low/overhanging tree branches? Is site free of weeds etc.? Is site free of weeds etc.? Yes 221

20 Are all signs easy to read? Are any signs missing? Have any signs been vandalized? Are any tree roots exposed on the trail surface? Are there any loose rocks exposed on the trail surface? Are there any sections of trail that require gravel surfacing due to slippery and unstable ground conditions? Has there been any damage to the trailheads? Has water damaged the condition of trail batters? Is the trail outslope at a consistent 5%? 222