...o meglio, lo dicono ma alla zitta: (dall' edizione online di Velonews,
http://www.velonews.com/tech/report/articles/5610.0.html
Flipping out
Wayne Stetina,
Shimano's R&D manager, says, "
If you remove the chain when it is only halfway worn out and flip it over," he says, "
you will double your chain life." In other words, your chain will now be turned inside out. The other side of the rollers will now contact the gears, and the derailleurs will now be laterally bending the chain the opposite direction. Stetina says that Shimano engineers discovered this phenomenon quite by accident.
Today's narrow chains do not allow you to push out any old rivet you want to accomplish this flip. Try it, and you could find yourself flat on your face! When you stomp down, the chain link plate could peel off of the end of the rivet. On Shimano, you need to use a new "subpin."
SRAM and Wippermann chains have a master link, which allows you to perform this flip very easily. Campagnolo chains come with only one link pin, and it is supposed to be inserted through a "virgin" hole in the open link at the end of the chain, so you cannot perform this reversal.