mine tumbles down rocky mountain roads at times. I've never noticed it gathering much excessive impact aside from what happens when a wheel rolls on its own shell. If it fell off the mountain, I'd imagine tire pressure will be a minimal concern. I havent studied the magnitude of forces, but even as it tumbles, the majority of the energy is spread along the tumble and not really too bad. Its all relative i guess. Newbies prolly shouldnt be riding up rocky mountain roads. In a side ways tumble, th