Thanks for your replies and to Carbking for such a detailed account of the differences in carb design. I'll have to give it some thought but I'll avoid buying the YF's and give up my original idea of buying another Roch B to go with a replacement I got a few years ago. It's a complicated subject if you're not an expert, but you've given me lots of useful advice. Dingo - feel free to take over this thread, and carbking - we have some lovely motorways in the UK, in particular the M1, M6 and M25. The trouble is they're jammed with cars morning, noon and night!
