Hi folks, please watch on what "Racer" you buy! NEN new bike and felt if the mounted Schwalbe Marathon Racer quickly and puncture resistant. Have previously worked flawlessly for years the Marathon Supreme gone without a hitch, although it now looks worse for wear, but has always kept tight. Now after about 100km I caught a 1cm piece of broken glass on the bike, the PROMT cuts me the carcass and the perforated tube. Puncture protection? how can that be? Tried to figure out with my tires and discovered that it is the lower-priced Marathon Racer "Performance" with the "Race-Guard puncture protection". This is by 2 layers of nylon fabric which has proved to be inadequate with me !!!! My advice: please buy the more expensive Marathon Racer "Evolution", which have the significantly better HD Speedguard- puncture protection (just like the Marathon Supreme ......) you Greeting, and many mishaps free kilometers ....