Greetings picked up a 60"s? Holdsworth trike conversion. serial number 1862.Original white paint and adjustable seat stays are chromed. Single drive set up for a fix gear. Does anyone know if the peice on the drive axel that the gear is screwed to is pressed onto the axel or is it threaded. I assume if it was threaded on then you would loosen it when you back pedaled to stop? Any way of dating this by the serial number?. Any help will be greatly appreciated. Take care ClemClem Skehan440 951 1053Willoughby Ohio