Blue, have you put any thought to tire chains? They're actually really easy to make, and are on my to do list. I've done them out of logging chain for my old dump truck. I've done them out of staples for 1:24 scale RC rock crawler. I guess a bike is somewhere in the middle. I've seen a premade set online, but they're pricy, and I'm cheap. A trip to the chain section at you local hardware store could save some serious cash. And maybe some skin.