how to make mountain bike dirt jumps

Technique: How to build mountain bike dirt jumps

28th Jan 2011 | 13:00

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Construction technique for tapletops and doubles

Winter’s the perfect time to build dirt jumps so they're ready to ride when summer comes. In this feature we'll show you how to construct a basic tabletop – the flat-topped style of jump seen in the picture to the right.

We'll then explain how to convert it into a double – essentially a tabletop with the middle chopped out – and, once you've mastered that, how to supersize it for bigger tricks. For tips on how to ride the jumps, see our Flow Like A Pro technique feature with Mike Smith.

Tools needed: Sharp spade, shovel, saw, brush, wheelbarrow, hoe, fork.

Rules: Only build where you have permission. Clean up after yourself.

How to build a tabletop

1 First up, thoroughly clear any debris, etc from the area where you want your tabletop to stand.

2 Have a search for dead wood that you can use to make a solid foundation to your jump.

3 Lay the wood widthways across the table where you think the centre of the jump will be. This will make it easier when you want to turn your jump into a double (the idea is that you can pull out the middle without affecting the takeoff or landing – more on that below).

4 Now you need a whole load of earth. Dig a hole as nearby as you can, and keep it big and shallow.

5 Load your freshly dug earth into a wheelbarrow and dump it over the logs to keep them secure. Carry on until they’re totally covered.

6 Level out the dirt using a rake or shovel and walk around on it to get it as compressed and as flat as possible, ready for the next soil load.

7 Once you’ve made the table, it’s time to shape it. Get the top as flat and compacted as you can, then use your feet to push the last two bike lengths of the jump into a gentle slope for the landing. Walk it down, then level it with a good whack from a flat, heavy shovel.

8 Shape the transition. Stand back and look at the top of the jump, the landing and how it meets the ground. Visualise the path your bike will take over that jump into the landing, and work out what the bike position at take off should be. A rule of thumb is to have a similar slope to the landing, only slightly steeper, and longer than your bike.

9 Start smoothing it out like you did with the landing, walking it and flattening it, keeping the curve smooth and the shape steep.

10 Shape the lip by rolling your bike up and down the take off to compact it, then use the shovel to smack it into shape. Start from the bottom and work your way over the ruts left by your tyres until your bike runs smoothly up and down and there are no bumps.

11 When you’re satisfied you've got the shape right, compact the top of the lip down hard and leave the jump to set. Rain and time will firm it down until it’s rideable – this could take as long as a week, but be patient. You might be riding this jump for years, so it’s definitely worth the wait. Good luck!

How to build small doubles

Once you’ve mastered your tabletop and are clearing it every time time, you can turn it into a small double, or gap jump, as it's also known. A double looks more difficult to jump than a tabletop, but it’s all psychological – they’re the same thing, just with less margin for error. And you can turn your tabletop into a double gradually, by lowering the middle a little at a time, to make it less scary. Here’s how to make the transformation.

1 Gradually remove dirt from the top of the middle of the jump – if you do this part in stages, it will help you get used to the feeling of jumping a double.

2 Remember those logs you laid down at the start of the building process? You can now pull these out from the middle without affecting the takeoff or landing.

3 Smooth everything out, and voila! You now have a perfectly shaped double.

4 Use the logs and dirt to make your next jump.

How to build big doubles

After mastering your small double, you’ll soon want something more challenging. A big double will give you more room for landing after ambitious tricks.

1 Firstly, make a plan. Aim for a 5ft-high double that’s about 6ft apart with a 10ft- to 12ft-wide landing. You’ll need a run-in that’s both clear of trees and smooth to ride. Your run-out will need space for building follow-up jumps too.

2 Collect branches and logs and saw them into convenient lengths. Arrange them in two piles, 6ft apart, to make a solid foundation.

3 Begin piling the dirt on, starting with the landing. Make sure the logs are totally covered. Tread the dirt down as you go and keep building the landing up until it’s 5ft high, 8ft long and 10 to 12ft wide.

4 Walk the back end down into a nice gentle slope.

5 Give everything a whack with a heavy shovel to pack it together (start with the back of the landing). Make sure the landing is at least a bike’s length long so there’s more room for error – two lengths is better.

6 Build up the takeoff and pack it with the shovel.

7 Shape the takeoff. The curve of it must be longer than your bike, and the shape needs to kick you into the air a little. Check out the diagrams above if you don’t understand what we mean.

8 Walk the takeoff into a smooth slope, run the bike up and down it to form a curve and then whack it down solid with a sharpish spade rather than the shovel.

9 Leave it to set and a few days later it should hold its shape when you walk over it.