rolling obstacles

How big of an obstacle can some of you experts “roll”, and at what kind of speed?

Also any advice on taking dips at speed will be appreciated.

I can roll stairs, if they’re the right shape:
http://gallery.unicyclist.com/albuo86

Being able to roll obstacles is very tied to the exact details of the obstacles. You really have to be there to compare.

For riding dips, you must be prepared to absorb the shock without your body being bounced upward. Sometimes this means squishing yourself down, so your feet can extend while the wheel pops down into the dip.

George Pendergast and I got to see John Childs roll something remarkable on Sunday. There was a concrete footing about 5 to 7 inches in height and about 12 inches wide after which it dropped maybe 4 inches. The footing had square sides so the starting angle and drop were literally 90 degrees or perpindicular.

There was a flat a few inches wide that followed the footing and the flat was immediately followed by a partially buried, 18 inch diameter steel pipe. The space between the two was just right to wedge your wheel hopelessly into. My estimate is that 6 inches or slightly more of the pipe was above the surface of the flat so the vertical starting angle was between 70 and 75 degrees for this second object.

John likes to roll things when we MUni so George and I wanted to see if he could roll this stunt with a trials unicycle on a 20" wheel which would make it somewhat harder. He had to cheat and measure the rollout but got it after about four tries.

George and I never made it over the two series stunt. I rolled to the top of the footing once and wedged my wheel in the space. I think George rolled the footing, too. Then we started cheating by hopping slightly.

JC rules the rolls.

Thanks guys,
It helps to see and read about what others are doing, and how to approach obstacles. There is tree with large roots and a drop on one of the trails I ride that sounds similar to the concrete/drainpipe obstacle. I have been wanting to try it and some tougher obstacles but have not figured out how to approach them at speed.