Dirt jump help.

Oct 31, 2016
Hey, ive been digging for a while but Im starting my first "legit" bmx trails spot. I have the first set done but I'm having trouble with the second takeoff's structure. The dirt on the back and sides is not stable at all, it's always cracking and collapsing. I'll add nice moist dirt and pack it hard but it seems like the new added dirt doesent combine well with dirt thats already there. Almost like there's layers. The dirt is clayish and has some rocks. Any advice?



Jun 14, 2003
Lost on Long Island
yes, it sounds like a layering problem. this does happen where if you layer, the outside layer will sheer off when it dries. Also, if the original dirt is junky, dig it out and back fill, you'll just never get junk dirt to pack and hold.

If the under-dirt is good then I suggest thoroughly wetting/soaking the original backside, then chunk it up by jabbing with a shovel to get rid of your nice smooth, packed surface, and increase the surface area for the new dirt to mix with and adhere to. make sure that now-very-chunky backside is good and wet (add water, wait for it to absorb, add water, wait for it to absorb, etc till its very packable but not pudding-y), and then start stacking and adding the extra backside dirt, which should also be packable-damp. I suggest making it thicker in the process, which also tends to help with cracking, so go ahead and add an extra shovel width, 10"-12" of depth to the lip.

If the lip is too thin, it might be the riding that is making it crack....