Turn signal excitement

Do I really want to keep a bike this old?  Yesterday I went out for a ride and the flasher unit failed (as far as I could tell).  OK, no problem... I picked up a new one ($3.99 at Advance Auto Parts -- I think they said it's a #552, and all of them should have it in stock) and installed it.  Huh.  Well, that's different.  When I turn on either turn signal, all four lights flash.

After a fair amount of tracing old wiring, I've got things to a point where the front turn signals work more or less correctly, and the rear lights both blink no matter what.

Oi.

Further updates as I figure things out...


Update:  OK, so I didn't figure anything out, but it's working now.

Here's what I can say.

When I disconnected the rear blinkers entirely (unplugged the connection under the seat) the front started working.  That seemed to imply there was a connection problem somewhere.  So I started unplugging things.  I started at the front of the bike, and undid every connection between the turn signal switch and the rear filament.  That means a couple of connections in the headlight bucket, the two under the seat, and a pair hidden behind the license plate.  Then I pulled the bulbs and put new ones in, despite the old ones clearly working.  Anywhere I found corrosion I scuffed the connectors with 220 grit paper (note:  doing this may make connections not fit anymore.  Be prepared to ruin electronics if you make a habit of this).  I found quite a bit of corrosion in the left rear light socket, and cleaned it out as well as I could with a piece of sandpaper wrapped around my finger.  It didn't work very well, but it made me feel better.

Once I'd done all of that, I turned the key on and tried the signals... and now they work.  I put everything back together, testing after each step (I figured if a wire was being pinched, I could find out that way), and with everything back the way it's supposed to be, everything works.  At least, for now...


As a side note, a big thank you to folks on http://hondatwins.net -- their advice and encouragement has been a huge confidence builder on this.  Also, to whoever rewired this bike in the past... please learn to do things right.  You're just making things harder on the rest of us.