dirt jump dimensions

Related:
Create New Tag

5/18/2017 4:42 PM

Hi everyone,
I`m planning to build a wooden jump(+wooden landing) in my backyard.
I spent a few hours researching, and found out that many bmx jumps(box jumps, dirt jumps)
are 5ft tall and have 8/9ft radius. That is an angle between 60 and 67 degrees.
But watching dirt jump videos and seeing trails in person, the jumps look steeper.
Does anybody know the accurate dimensions/angle of a steep dirt jump?
Thanks

|

5/18/2017 8:51 PM
Edited Date/Time: 5/18/2017 8:51 PM

Photo

I built mine 7 feet tall and ten and a half long , just reworking the runway and dirt landing to it this week
It works pretty good
|

5/19/2017 1:03 AM

It depends on the size of the jump, height and lengtha. But also where it is in the line and how fast you'll be going. Most trails builders change things fairly often, building up a landing, mellowing a lip. It depends how it rides

|

5/19/2017 1:20 AM

dirt jumps aren't built with a compass and measuring tools like box jumps are.

Most of the dirt jumps we build around here have a six foot or taller lip.

The size of your box jump will depend on the space you have. Do you have enough room to get speed for a five foot tall box? Can you jump a five foot tall box? etc.

|

5/19/2017 10:32 AM
Edited Date/Time: 5/19/2017 10:34 AM

This is a good thread to check out:

Wooden Jumps. With pics
https://www.pinkbike.com/forum/listcomments/?threadid=29852&pagenum=96

Also, check out this thread on roll-ins. Unless you can crank down a driveway from the street or something, you'll probably need a roll-in, right?

http://ridemonkey.bikemag.com/threads/roll-ins.228191/

|

5/19/2017 12:26 PM

Thanks for the replies, speed shouldn`t be a problem. The roll-in is 10feet high(from the top of a garage), and I can get a few cranks in before I hit the ramp. I planned for the ramp to be about 6 1/2 ft tall with a radius that is 1.5 bigger. I was just wondering if dirt jumps tend to be steeper, if the radius is only about 1.4 bigger than the height?

|

5/19/2017 1:25 PM

Build it, ride it, adjust it. That's the beauty of dirt. The length is a pretty important factor. A real steep lip will send you up but not across. So you'll go high but might hook up all the time if it's a long jump. How a jump feels is personal preference

|

5/19/2017 2:30 PM

grumpySteve wrote:

Build it, ride it, adjust it. That's the beauty of dirt. The length is a pretty important factor. A real steep lip will send ...more

This. With dirt it does not cost more than time to change it up (but tends to have more maintenance)

|

"Hey anybody ever make that mistake like right when you wake up in the morning and you believe in yourself?" -Kyle Kinane

"BIKES!" -Tom Segura