3rdCoastPowerSports

iTrader: (5)

Why would you do a crank re learn?

gMAG

iTrader: (1)

* EEPROM was reprogrammed.
* If Diagnostic Trouble Code (DTC) P1336 exists.
* If crankshaft, crankshaft position sensor, engine, Powertrain
Control Module (PCM) or vibration damper have been replaced.

This was from a maint CD for my 98 engine.

3rdCoastPowerSports

iTrader: (5)

so if i pulled the motor out and completely rebuilt it due to a spun bearing do i need to do a crank re learn.

gMAG

iTrader: (1)

As long as you didn't change any of the components listed above. Changing any of them would alter the already established relationships between them.
The CKP sensor/crank variation info is stored in the PCM. I've disconnected the battery, and disconnected the ECM, and this did not generate a P1336 code, either.
Does repairing an engine cause the crank to behave differently than it did, previously? I don't know.
I'm in the process of rebuilding mine, as well. And, I'll probably perform this step anyway. Sorry I can't be more exact.