Bridgestone Corp. (TYO:5108) has begun sales of the Battlecross E50 Extreme, a new tire for motorcycle enduro racing. Launched on Nov. 1, this new offering has been made available as a rear tire with the size of 140/80-18 70M. It is made specifically for competitive racing specs, and so cannot be used on public roads. The Battlecross E50 Extreme is…