ORIGINAL: windowlicker
think you want thin for loose and wider for hard tight surfaces. The thinner the tyre, the more pressure it will put down on its narrower surface area. Wider tyres have less pressure due to their wider contact area with the ground. Narrower tyres in most cases will bite better, wider will have a tenancy to slide a little more.
Correct me if I'm wrong, I don't race, I'm just using my poor knowledge of physics!
That makes sense (just like real tires). So for hard, dry conditions, wider is better. But for slippery surfaces, narrower is better. At my local track, narrower is probably better as the track is hard packed dirt (really hard) with a very slippery thin top of loose dirt. I'll try both. Was mainly wondering to decide if I wanted to get a 2nd set of dirt bonz to dedicate to the truggy.