Several vendors sell these things, they are inserts for the front axle, right side and I am trying to figure out if there is any real need for this tool, on this bike in particular. I could see if the axle threads in the the left hand leg and it would require you to tighten the axle with the hex tool. I understand if the axle was spinning and you couldn't tighten it, but I've never run into that. ?????? Any other purpose that you can think of? The lower aluminum section of the fork that clamps onto the axle is pretty tight and I've experienced some difficulty reinstalling the axle. I've used a thin bladed screw driver to try and expand the clamp, but it is difficult. My concern is that the right side fork will not be able to moved in or out when you attempt to center the forks?