oldhead,

Without a serial number not able to verify size of drive tire. If you installed the correct size, the tire must be pressed on exactly as it came off. The wheel is set into the tire about 1 inch. The drive unit will need to be set at the correct angle to get the new tire installed. It can be aggravating. Since the tire wheel combo weighs enough to make it hard to handle. There is no adjustment that can be made. Good Luck.