I rebuilt my daughters cb750 last summer and found the small rubber wheel timing chain guide was crumbling. what to do had an old box of 70's era cb450 so i used my drill and drilled the rivet from the metal cogged timing chain guide wheel. grabbed the cb750's and used pliers and crushed in the braded pin and slid it out and put the cb450's {wheel} on. works great now i dont have to worry about another piece of rubber.