47mm is minimum but only really works if you run higher psi, which defeats the float advantage of wider rims. Even I, sceptic and cheapskate that I am, accept this. Thus I've bought 65mm wide rims from Robsson which will be a half way house from present 50mm rims to the pretty much norm 80mm. My rims cost £70 delivered for a pair, there in DHL transit as I type. As for 170 v 135mm hubs this for me is not an issue as I'll be fitting them to a frame I'm custom bodging and thus will tailor whats available to my needs.
If your the patient type, sit back and bag the components you need as and when they become available at a price your happy with, that frame for example.
