How to adjust idle speed on 49cc scooter Have more questions? Submit a request 2 Comments Date Votes 0 David W September 15, 2016 01:15 Where is the CDI located on a 2016 Thunder 50? And the spark coil? Thanks. 0 Wesley Matthew Webb September 07, 2019 14:39 It's in-between the battery and the mother, and I think if you follow the wire that comes straight out of your spark plug it's under your seat. Please sign in to leave a comment.