ecco qua la spiega...in pratica per risparmiare qualcosa..
The 2011 R-SYS SLR features the new Exalith rims front and rear, and is available in tubular or clincher versions. The clincher system has a claimed weight of 1,994g (the wheels alone weigh 1,370g) and costs £1,330/$2,000. The tubular...