Motorcycle Repair: 1990 honda cb 1, honda cb 1, battery terminals

Question
what does a rectifier do and how would i know if it's shot

Answer
Hi Kyle.
 The rectifier takes the Alternating Current that the stator produces and converts it to Direct Current that the bike uses.

 Usually, they do not go bad.  However, if they do, they generally show voltage as AC on the battery terminals.  It should be DC.

Hope that answers your question.
Ride safe.
FALCON