Trail building is an integral part of being a mountain biker. Whether it’s creating a line from scratch, adding a feature or two, or simply maintaining what’s already there, every mountain biker plays their part. Pro mountain bike athletes like Thomas Genon, Matt Jones and Gee Atherton are known to get their hands dirty to make sure they have the perfect line in their filming projects..
Explore the craft of trail building through the eyes of some of mountain biking’s best riders and most respected builders in the film Builder below:
With the help and recommendations of Nikki Whiles from British-based trail building firm TrailCraft, we take a look at look at the basics of trail building. Whiles has expert know-how and was involved in digging for the dream line of Loïc Bruni‘s that features in the Frenchman’s segment in the film Gamble. Here are a few things to consider before you get stuck in.
1. Know your hill
First things first, what line is your track going to take? No matter what the area you have to build on looks like – mountain, hill, steep, flat, forest or not – you’re going to need to spend considerable time getting to know every available feature, planning lines, plotting your route and noting the good bits and the must-avoid bits.
“What’s especially important is walking the hill or area a lot. If you’ve got a hillside you want to build on, I recommend you walk it until you know every inch of that hill – best features, gradients, etc. We GPS stuff and use every tool possible to help get an idea of the hill before we pick a route,” says Whiles.
“Once you’ve picked your line, you’re stuck with it. You want to avoid any kind of wet ground – stay high and dry if you can. Sometimes you’re forced to take a bad route down a hill, but then the beauty of hand-built tracks is that they’re nearly always on a good route with good ground, because it’s so hard to build by hand.”
If you’ve built a mountain bike track before, you’ve probably learnt this lesson the hard way, whether you realise it or not. Good drainage is often overlooked and the ensuing erosion and rapid destruction of a track perhaps isn’t always accredited to initial trail design. When you’re picking a line for your track, always think about where the water will go and you will help guarantee greater longevity for your creation.
Whiles explains that a common technique in trail centre building is the grade reversal – essentially making sure there are few flat spots for water to gather and deliberately building dips and hollows into the trail, towards which the water will be sure to run and then exit the track.
“Drainage is absolutely paramount. Constantly think about where does the water run? You want to avoid sizeable flat bits of trail – if it’s going up and down, water will always run off. Try to avoid drainage pipes as they tend to just clog up. Building features like rollers can help send water off the trail,” advises Whiles.
“Long sections with no features can cause really bad water erosion. In Madeira, when we were building Loïc Bruni’s Gamble line, I met with the local government to talk about drainage because they didn’t want a mountain bike track to cause flooding – long runs with no planning can become channels for water.”
3. Creating flow
When choosing the line of your trail and working on the initial build, you’ll probably be looking to create that highly sought-after riding experience: flow. Maintaining speed and ensuring everything links together is the key to flow, particularly where flatter trails are concerned – steeper tracks can afford to stop and start, as the gradient will quickly get riders back up to speed.
“You don’t want to be braking loads, losing all your speed and then having to build it up again,” says Whiles. “Well chosen and built features can make a trail feel flowy – nice snappy turns, rollers, roller doubles – two rollers close together that you can either roll, manual or jump, etc. I’d say nice features that link together without having any dull sections, where you keep your speed, that makes a good, flowy feeling.”
Watch a perfect example of a good flow trial in the player below, featuring the Flow Trail in Zermatt, Switzerland:
4. Bench cuts
If you’re working with a steep hillside and don’t want to go straight down, you’ll need to bench cut the trail. This means digging the trail into the hillside to create a bench profile in the hillside. Naturally, this can equate to a lot of water gathering on the trail, so be extra vigilant in creating features designed to channel water off the trail and make sure to include plenty of undulations that will force the water to go exactly where you plan.
“On a flat bench cut, you’re going to need a camber on it in order to make the water run off, but what makes the best flow is a trail that really holds you in and an opposite camber can feel horrible,” explains Whiles. “Making the trail go up and down is the key, then you can also build features that help drainage.”