They do go bad I had a throttle body set up go bad on the r6 at about 53000 miles. Bought two of them off ebay to fix it. The first one was good but needed a screw adjustment that i wasnt aware of it on that particular model with an adjustment. Screw is not on any manual or anything to do with the bike. I did look up the actually throttle body and found a can am quad with it on a forum and they mentioned it. The second one i bought was bad i out the first one back on adjusted the screw and it was good to go!!!! The original was definately bad. It would close completely cutting off all air and fuel to the motor.