My bike is a 520 with bar end shifters. I flipped the bar upside down so I had to remove the shifters and breaks and put them back on. Now when I am climbing the mountain in granny gear the chain or something is slipping when i get to a real steep section and have to peddle hard. Just from flipping the bike over and running it down to the smallest gear it lookes like the rear deurailer is over far enough. I can go up one gear and it does not slip. I have not tried to adjust anything but it is agrivating. I can make it up the mountian in the next to lowest gear but it is harder. BTW here is the thread from when i flipped my bar. As you will see, I am not a bike machanic.