Bridgestone's Kobayashi on the 2010 tyre changes

Bridgestone's Kobayashi on the 2010 tyre changes: "This week's Valencia test was the first opportunity for the teams and drivers to sample Bridgestone's 2010 specification Potenza F1 tyres. The new front tyres are 20mm narrower than 2009's - a move designed to redress the balance of the cars after grooves were removed for the start of last season. With refuelling now banned, the rear tyres also feature a new construction to cope with cars that will be heavier for longer during Grands Prix. Tetsuro Kobayashi, Bridgestone Motorsport's technical manager, explains more and reviews testing progress…"