I have done this repair on various ATVs. It is best to buy the tool if you can find one, but it can also be made from an old socket or lug wrench as previously discussed. If you can't buy one or make one, you can use a big punch or something similar as a last resort, but it's not recommended. I have done it successfully, though. Note that you only have to break the lock nut loose. You don't have to turn it all the way off the pivot bolt as it will turn on off with the pivot bolt when you take the pivot bolt out. Make sure you're allen wrench or allen socket fits the pivot bolt real good, because on a lot of ATVs they are extremely tight. If it slips and rounds out the bolt head, you will have a big problem. Sometimes one will not be extremely tight, but I have found this to be rare. Also, when you get the bearings in the swing arm and start reassembling it, be careful not to tighten the right side pivot bolt too tight, as you can damage the frame and cause the bearings to go out prematurely. As you tighten the pivot bolt, if you tighten too tight, you will see the frame start to bend out and you will see the space between the swing arm and frame starting to get bigger. You don't want this to happen. You just want to tighten the pivot bolt down snug, but you will want to tighten the lock nut real night. I don't know the exact torque for it, but it needs to be real tight. You will need to hold the pivot bolt with an allen wrench or socket, to keep it from turning, while you tighten down the lock nut. It's a good ideal to mark the pivot bolt and the lock nut with a punch or chisel, so you will be able to look at it and make sure it hasn't loosened up. After you ride it for a little while, check it to make sure it hasn't loosened up. Sometimes they do, if you didn't get the lock nut tight enough. Keep an eye on it every time you ride it for a little while, to make sure it isn't going to come loose. Good luck.