Why are Dirt jumps so scary, and what is a Jump Jam anyway?

I will confidently say I am an enduro rider, I enjoy a bit of Downhill and general trail riding, but I know where my strengths are, and they are not on bikes with little wheels, flat pedals and mounds of perfectly sculpted dirt. So when I decided to try a bit of dirt jumping, to expand my skill set, I was understandably nervous.

Gorge road jump park – Redbull Media.
Yes I have ridden here…but only the very baby line.

I have a good base set of bike skills, but the jumps that I normally ride on the trails tend to be long and low. You pedal as much as you can get away with, then pull up just enough to cover the distance. It’s all about the forward momentum, not so much about how much upward momentum you can generate. Dirt jumps on the other hand, are designed to send you up in to the sky, and pedaling in to them is like riding your bike towards a brick wall, with an equally big brick wall behind it, that you absolutely want to clear. The lips of the jumps are steep, and the landings are almost just as steep. Instead of the long mellow pathway you want to take on a trail jump, these will send you to the moon, and you need to have the confidence to nose the bike back in towards the landing in a graceful rainbow arc. That’s the idea anyway, and for someone who has always aimed to keep the bike steady and in a straight line, this arcing motion is just another consideration to add to the mounting pile of fear.

Jumps found on trails tend to have long and low arcs, and require more speed to clear.

Dirt jumps have a shorter, but higher arc, they require the ability to generate lift to clear.

Dirt Jumps are a work of art, carefully sculpted to the perfect geometry to make the jump feel smooth, whilst giving the rider as much ‘air time’ (time when your wheels are not on the ground) as possible. The idea is, that the more air time you have, the more time you have to perform tricks. Because of the shape of them, a lot of work must go in to maintaining the jumps. Regular watering and slapping them back in with a shovel keeps them in good condition. Many places put tarpaulins over them when not in use, to prevent them drying out and cracking. In order to not break the jumps up, most riders opt for smoother tires, with very small tread pattern. This also increase the rolling speed so that you don’t have to pedal in between jumps. You know it’s a good jump line when, as long as you get the first jump smooth, you shouldn’t have to pedal at all, to clear the whole line.

Obviously everyone had their different preferences, but this is an example of the geometry of an average Dirt Jump bike.

As well as smoother tires, jump bikes tend to be a lot smaller than trail bikes, with steeper geometry angles, 26 inch wheels (unlike the more common 27.5 or 29 you find on enduro and downhill bikes), and their saddle is as low as it will go, to keep it out of the way. They also have have higher tire pressures, and much stiffer suspension set ups. All these features are there to make them roll fast and generate lift of the jump. One final thing are the flat pedals. Although flat pedals are still fairly common amongst trail riders, I haven’t used them for many years, and have to make a conscious effort to now try and keep my feet on the pedals and in the right place. I have been known to make the sound effect of ‘clipping in’ at the top of a trail, just to trick my brain in to thinking I am still riding clips.

Learning to back-flip on the local airbag at Velocity Valley

I have always enjoyed the jumping aspect of ridding bikes, but I had never taken it very seriously. I own a jump bike, but so far I had only used it for learning tricks on the local airbag. So I was in an odd position of having a bit of experience, and a small trick bag, but never actually taking any of it to the dirt jumps, so when I was invited down to the local dirt jump spot in Rotorua, I jumped at it. After all race season in the southern hemisphere was over, so it would be a nice change of pace to riding long distances in the rain through autumn. I wasn’t going to pressure my self or set any goals. I accept I am a slow learner, and I don’t do well with peer pressure, so I went along just to see what it was like.

A lot of well designed dirt jump spots have multiple jump lines. These are row of jumps that all line up with varying levels of difficulty. Most dirt jump parks have progression lines, which are smaller, with shallower lips, and often don’t have gaps, so the chances of getting it wrong is quite low. On my first visit I was quite content with just riding the table line (no gaps), once I was comfortable with that I managed to clear the end gap. This did exactly what it was supposed to do to my confidence. I was so excited about hitting it, and after a couple of runs it felt so comfortable that I then started doing what most people do, which is look at the next step – the main line.

The mainline is intimidating, it’s much steeper than anything else I have ridden, and once you are on your way up that take off there is no backing out. I rely on friends and people who are better jumpers than me to tell me if I have the right speed and ability to clear something. So with a lot of encouragement, I dropped in to the line, and after a couple of dummy runs to judge speed, I went for it. Now I am the first to admit I have commitment issues when it comes to clearing new features. I over think them, and chicken out 10 times before I am sure I can do it. The trick that works for me is to try and forget about the landing, or what to do in the air (I have enough experience on a bike that my muscle memory tends to take care of that), all I do is focus on the lip of the jump, if I can just aim for the middle of the take off everything else falls in to place. And it did. Once I have cleared a jump for the first time, all that fear lifts, and then the second one in the line came quickly after.

So this brings me to the Jump Jam. I had heard of them, but never been to one, and didn’t really know what they were. Some friends found about about one being held at the Spa Park Dirt Jump park, about an hours drive away, in Taupo, so we all decided to go along. I was expecting it to be really intimidating with lots of amazing riders (which there were), but it wasn’t intimidating at all. There were 50 riders or more, with a wide range of skill levels, just chilling and doing their thing. Although there was a high jump and trick competition, that wasn’t the focus of the event. It was more about having an afternoon with all your mates, just doing laps of the bike park. It’s also about eating lots of burgers and raising money for the maintenance of these jumps.

Sticking out of the ground like tomb stones – the Pro line at Spa Park, TaupoRobbie Dalziel Media


I put no expectations on myself, although these jumps were a little smaller than the couple I had cleared in Logyard, I had never ridden the Taupo dirt jumps before, and was not keen about hitting them with such a big crowd. But it was inevitable that once I got comfortable, and soaked up the hype from everyone having a great time, I was loving the challenge of getting through the line. Luckily I have lots of talented friends to discuss just how to approach them, and they were able to check that I was coming in at the right speed, that made it all a lot easier. At the end of the day I am really happy with how far I got (even though it took me lots of run in’s before hitting the ‘send button’), but I did manage to clear the first two jumps on the middle sized line. I would have easily gotten the third as well, but by the time I was ready to try, the organisers were erecting the high jump competition on it, and there was no way I was about to hit it for the first time, when it was surrounded by scaffolding.

The fires are truly stoked, and I cant wait to come back and clear the rest of this jump line – Spa Park

I think these guys have an anti-gravity switch on their bars Spa Park, TaupoRobbie Dalziel Media

Overall I think that learning to Dirt Jump has been a great boost to my bike skills. It has improved my ability to judge the exact amount of speed and pop I need to clear a feature, and it has taught me to read the terrain in a totally new way, but more than anything it has boosted my confidence on the bike. If I can do this, on a twitchy little bike, with flat pedals, then when I jump back on my big, slack, enduro bike, I feel like I can take on the world. I fully intend to keep on dirt jumping whenever the weather permits, it’s great fun, and good change of pace compared to the long miles spent on the trails. I can confidently say, I am now a dirt jumper.