i have been having problem with the little square drive keys for the speedo breaking on my 2004 switchback 700 144, i replaced one and it last about twenty miles, went to replace it again and could not get it out, so i to the whole jackshaft out replaced the bearing, but part of the key was still stuck in there so i just trimmed the new key down, that one only last about a 100 miles, does anyone no what could be causeing this.