I'm building a wind skate to use on the beach on those very light days. Planning to use rubber tyred wheels on skateboard trucks. Wheels will be at least 4 inch, maybe bigger. The widest skateboard trucks offered by retailers appear to be 10 inch. Is this correct? I haven't locked in the dimensions for my board yet but I'm thinking I'll need trucks wider than that. Local skateboard shop owner agrees, and he isn't aware of anything wider. What do people use on this style of board?
Put the wheels u need on some pipe then weld that to the trucks' stub axle (toe in possible to tame the speed wobbles)
or put the wheels on like 40cm of pipe an u-bolt that to the trucks' underside (easier to get straight, and adjustable if u didn't nail it first time)
its important to have the right wheels so get what u need then adapt onto anything, bloody Kmart trucks even
There is a french company that sells very wide trucks for wind skating but for some reason I am struggling to find the link
If you can find some mountainboard trucks & wheels, I think they're a bit wider and wheels are 20cm. I think some offer looser and stiffer options of bushes, which could be useful for your windskate. Brands include MBS and Trampa.
Oh and if you won't always be on the beach, I found u need to buy some spare skin too 
Windskate was probably the most terrifying board I've ever ridden. Then again it was early on.
