Guy's, please explain something to me.
I am no expert at all and I enjoy watching the Motogp so much that I don't miss any of the races but I cant understand why Rossi had problems with his tyres because if I am not mistaken he was also on HARD front and HARD rear like 90% of the other riders and non of the other riders was so badly affected than him.
Tyre degradation is affected by several variables, mainly track temperature but also bike set up and riding style. Bike set up referring to front vs rear weight bias and riding style referring to braking style (late hard vs early smooth). Other factors like corner speed and lean angle also come into it. Bike set up gets very finicky when you are searching for tenths of a second. You change one thing slightly and something else goes off.
Each rider has a predominant riding style and depending on the track characteristics on the day, that style can work or not work. Really good riders can modify their styles to the conditions but it's a hard thing to do. Biaggi and Pedrosa for example find it very hard to adjust their riding styles. Rossi, Stoner and some others can change quite quickly, they can ride it lose, ride it in line, ride it sideways, etc etc.
Now coming to the Rossi tyre issue, he was off the pace all weekend, just before the race he changed to a set up that they hadn't tested, hoping it would give him better pace but what it caused was excessive tyre degradation and the gamble didn't work.
See article below for an interesting read on Scott Redding struggles with set up :
http://www.crash.net/motogp/news/245369/1/redding-this-bike-is-such-a-fine-line.htmlAnd Rossi here:
http://www.crash.net/motogp/news/245340/1/rossi-yamaha-doesnt-have-good-marriage-with-tyres.html