I've had plenty of success getting non-UST tyres to run tubeless on Stans and UST XT rims - but, I'm wondering if anyone on here has tried UST tyres on non-UST rims (i.e. Stans, American Classic 'tubeless' MTB).
FWIW, at the moment, the AC rims have Stans yellow tape and I'm temporarily running a pair of fairly old threadbare non-UST Kenda tyres with Stans fluid. (seen a good deal on some UST tyres that I fancy trying)
