The HARD-wet Bridgestones started chunking on the drying Motegi track last year. The HARD-wet Michelins did not chunk at all on the drying Brno track. So far, the Bridgestones look worse than the Michelins.
Attempting to facilitate such comparison between the two tyre manufactures/ products is futile - particularly given the myriad of vastly different variables not least the track characteristics, circumstances, prevailing conditions and surface - (although the latter is less pertinent in the wet). Motegi is a completely different prospect to Brno and a fierce unforgiving stop/start, hard braking circuit.
On reflection, my last post and response to Michael was perhaps too sceptical in recollecting the circumstances governing changes to the carcass in 2012. With all this discussion of chunking, it has occurred to me that there post revision to the front, there still remained very real fears for safety. In 2012, the new formula meant that the bikes were heavier, faster, and more importantly, had increased drive lower in the rev range. In view of the huge advances made in electronics during the 800cc era, this exacted much greater loads on the tires than Bridgestone had envisaged. Better mechanical grip from the bikes, and purchase from the added weight and new tire design resulted in the tires to start showing signs of overheating. Despite the changes to the rigidity of the carcass creating an easier to manage front – serious problems still afflicted the rear. Remember at Assen in 2012? - rear tires were hurling chunks of rubber like shrapnel. Ben Spies finished a long way from the podium with rubber shredding off his tire, and Vale was forced to pit for tires. Viddu, tires coming apart in such a way is not an acceptable situation, particularly indiscriminately and randomly as they did on Sunday whatever your contention about the drying track. Blistering on the surface is one thing, but when you’re throwing major chunks of rubber down to the carcass that cannot be attributed to riding style or the fact it stopped raining. Remember, although the soft wets are designed to work best in torrential rain, they should still be in their tolerance on a wet surface and cooler track temperature. Watch the race again, Dovizioso’s failure was sudden and instantaneous occurring well within what should be the performance envelope of the tyre.
There's great secrecy about the way moto gp tyres are made by both manufacturers, I am just taking an educated guess that the 'glue' Bridgestone use could have a higher melting point.
You’re serious aren’t you? Sorry, I’m not being unnecessarily vitriolic, but I thought that was a joke! However, it does introduce an interesting point. Remember the contentious heat resistant layer? Realising in 2012 that Bridgestone had a serious issues that I highlighted, they formulated a layer in the tyre intended to prevent the inner carcass from overheating through dissipating the load better. Their introduction was piecemeal initially, Motegi being an example, which as I mentioned is particularly hard on tyres. By 2013 I believe I’m right in saying they were introduced at all circuits in the calendar. The upshot was however, at lower track temperatures with diminished grip on the edges, there were problems with feel. Guys like Marquez, who square off the corner saw little discernible difference but Jorge with his traditional lines and high corner speed was struggling. Hence the edge treatment introduced in 2014 which again was used selectively at those circuits which generate less load on the tyre but lead to the misconceptions amongst Rossi aficionado’s on here that Bridgestone were manufacturing tyres exclusively for Lorenzo. Meanwhile, Jorge was venting spleen whenever they arrived without them.
Low melt temperature adhesive??? I don’t think so, but it does lead me to question if Michelin have followed Bridgestone’s lead in incorporating a similarly designed heat resistant layer on the carcass and if so, whether it is inferior. Entirely my own speculation, but given the growing catalogue of failures this year, particularly the delamination issues, I suspect this may well worthy of further consideration.
