This is a pretty cool direction too. I like the abstract V that is representative of treads, whether it be bike tires or running shoes. Even the "A" looks tread-like. Pretty cool. #7 is uber-cool concept, but my concern on that is readability.
#8 looks like it might be more automotive related or at least bike only. I wonder what it would look like if the V elements were flipped an used as the "A" in Tread, and maybe in Threads as well.