Loosen and remove screws from lock mount.
Position shim and the mount over the top tube. Cut the shim in half or less than half for it to fit.
NOTE: Lock mount release button will be on the rider's left.
Re-insert screws and tighten.
Tighten the screws inside the inner part of the lock mount to make sure they are secure.
Mount the lock.
NOTE: Due to the weight of the lock, the mount screws will strip and split the mount if you put it on the seat tube. Please use the top tube to mount the lock.