April 2011 excerpt from a Lizrdbrth post:

"First Gen, if you will was 1987 only, first year of the TW. It had a separate lighting coil, the lights only came on if the bike was running. It had no front running light feature and the safeties were wired slightly differently from subsequent runs. It used a 1987-specific CDI unit. The left engine sidecover only accomodates the 1987 charging/lighhting system."

Very useful info; i just wanted to make it easier to find in a search.