thanks for the reply plummet.
i agree that the twistars won't work cause they need the pressure... why are they cheesy, cause they are plastic? it's all new to me. when you say henious do you mean in terms of just the weight? if i don't do any jumps would it matter? speed wobbles anyone? a diff of even 2kg per tyre would only be the diff between a few large meals!
thick walls are possible, i've seen that for bikes, but thick is still only about 5mm, these suckers were around 1inch long, crazy!
i'd love to have the peace of mind of solid tyres over this nasty terrain. the primary challenge with "solid" wheels would appear to be the sheer mass. given they need to be 200 x 50 mm this is really saying i want a low density tyre, but with good wear - ie. a contradiction!
just had an idea - a tradeoff is a small diameter of solid rubber around the edge of the wheel. i've seen car tyres like this, big mags with a little strip of rubber tyre around the outside...
ok did some google-ing, now this is something! i'd like 4 of these in 200 x 50 Mr. Michelin please!
http://auto.howstuffworks.com/tweel-airless-tire.htm
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