The grand prix 4000s ii boasts global appeal as the best all round race bike tyre on the market not only is it fast and super grippy thanks to its state of the art blackchili rubber compound but it is also tough with a healthy tread layer and of course continentals vectran anti puncture breaker layer underneath so for reliability longevity and all out performance for your race machine the gp 4000s ii is the only choice how are these figures possible the carbon filler particles within t