You're correct, except you'll also need the flywheel/rotor from the later motor. Pretty much an afternoon's work.
The only difference remaining is the automatic cam chain tensioner. If you want it can also be transfered over to the early motor while the side cover is off to swap flywheels.
But don't throw the baby out with the bath water just yet. Find out why the late model motor won't turn.
I'll offer two possibilities. To check either on a bike which has been sitting for awhile you should remove the spark plug, put a couple of tablespoons of ATF down the plug hole and let it sit overnight. That will help minimize any scarring of the cylinder if there is any rust haze in the bore:
1. Best case scenario: The starter relay has failed or corroded and is arcing internally. Easy test. With a full charge in the battery, freshly cleand and tightened battery terminals and the bike in neutral just jump the two big wires with a 10 gauge wire, one side of a set of jumper cables or even the points of an old pair of needlenose pliers (Key doesn't need to be "on" for this). If the motor spins replace the relay. But don't replace it with a late model solid state relay. Use either a mechanical one from an early TW or one from a larger bike. Late model TW relays are doodoo.
2. The motor sat for a long time and the rings have siezed to the cylinder. Do the ATF thing, then next day rock the bike forward and backward while in third or fourth gear. Don't force it, just bump it and see if the crank moves. Let it sit, repeat. Sometimes you'll get lucky, but most times you'll still need to do the top end just for peace of mind. You'll need to free it up regardless in order to get it apart once it's out of the frame (It's actually a good idea to follow this procedure on any unknown motor before firing it up).
If it's rust siezed the engine swap is probably your easiest and cheapest alternative. One shortcut is to do the flywheel swap while the both motors are still in their frames with the chains hooked up. Put the tranny in fifth gear to remove, replace and torque down the flywheels. If you don't do this in advance you'll have to wrestle with finding another way of keeping the motors from turning.
The only difference remaining is the automatic cam chain tensioner. If you want it can also be transfered over to the early motor while the side cover is off to swap flywheels.
But don't throw the baby out with the bath water just yet. Find out why the late model motor won't turn.
I'll offer two possibilities. To check either on a bike which has been sitting for awhile you should remove the spark plug, put a couple of tablespoons of ATF down the plug hole and let it sit overnight. That will help minimize any scarring of the cylinder if there is any rust haze in the bore:
1. Best case scenario: The starter relay has failed or corroded and is arcing internally. Easy test. With a full charge in the battery, freshly cleand and tightened battery terminals and the bike in neutral just jump the two big wires with a 10 gauge wire, one side of a set of jumper cables or even the points of an old pair of needlenose pliers (Key doesn't need to be "on" for this). If the motor spins replace the relay. But don't replace it with a late model solid state relay. Use either a mechanical one from an early TW or one from a larger bike. Late model TW relays are doodoo.
2. The motor sat for a long time and the rings have siezed to the cylinder. Do the ATF thing, then next day rock the bike forward and backward while in third or fourth gear. Don't force it, just bump it and see if the crank moves. Let it sit, repeat. Sometimes you'll get lucky, but most times you'll still need to do the top end just for peace of mind. You'll need to free it up regardless in order to get it apart once it's out of the frame (It's actually a good idea to follow this procedure on any unknown motor before firing it up).
If it's rust siezed the engine swap is probably your easiest and cheapest alternative. One shortcut is to do the flywheel swap while the both motors are still in their frames with the chains hooked up. Put the tranny in fifth gear to remove, replace and torque down the flywheels. If you don't do this in advance you'll have to wrestle with finding another way of keeping the motors from turning.
