Turn signal problem and now no ignition - wtf?

The other day I went to tighten my left-front turn signal inside the headlamp. After doing this I turned the signal light on and instead of the front and the back blinking like their supposed to, the front turns off entirely and the back is on steady, not blinking.

Not knowing exactly what to do about it at the time, I rode for about 20 blocks then blew my 20A Main fuse. I opened the headlamp back up to try to find a short but couldn't find a single thing that looked suspect.

After blowing three more fuses I somehow got the bike going again and made it 3/4 km from home only to have it blow the fuse again. This time, after putting another fuse in, the starter button stopped working and roll-starting the bike didn't work either because I wasn't getting spark. Seems as though no power is getting to the ignition system. I do have power to the lights however.

Pushing the 650 uphill for a km was good exercise.

I have since installed the blade type fuse setup and cleaned the contacts on the battery because they were very corroded. Before cleaning the contacts I noticed the lights would flicker on and off when wiggling the positive lead. After cleaning it this stopped. Most other contacts on the bike seem in fairly good condition.

Regrettably, in the process of trying to get the bike home I put a 30A fuse in the 20A main only to blow it as well. This was only in there for a few minutes. May have caused other problems though.

If I bridge the solenoid, the started turns over but the bike doesn't fire. Again, because I have no spark.

Bit of an electrical nightmare on my hands. Not sure what to do at this point. But either this is a coincidental breakdown of isolated elements or they are all connected somehow (with wires or something). I tend to think the latter.

Thanks.

You start your post by saying "The other day I went to tighten my left-front turn signal inside the headlamp."
What do you mean here? Tighten the bulb? The wiring? The brace nut for the turn signal housing? Would help to know what you did. Sounds like a short of some kind.

The nut that holds the signal housing inside the headlamp. I tightened that.

Check to see if you're getting any juice out of your Dyna S. They don't take very kindly to spikes in current, and if you were creating enough of a spike to pop a 30 amp fuse you very well may have cooked the pick ups on the Dyna.

Other than switching to the blade style fuses (which you did) and checking and cleaning EVERY connection on the bike (a bit of work but well worth it) troubleshooting the Dyna is about all you're left with.

Blowing a 30 amp fuse repeatedly in a short amount of time= a short circuit of B+ to ground. Look for where you have the short. Do you have a manual with the diagram for your bike?
Try removing all of the fuses, noting where each size goes, and first installing just the main, then the ignition, lights, etc. until it blows again. This might help with getting it running, and which circuit has the problem.

I tested the voltage on my Dyna and did not see a battery level spike in voltage when positioning the rotor magnet at the pickup. According to Dyna this means either the Dyna is dead OR the output is somehow shorted.

My money is on the Dyna being dead after the repeated spikes you were talking about. You can send it to Dyna and they'll refurbish it for somewhere around $70, or replace with a new one, or if you want a little heartier system source a OE Kaw electronic from an 81 or newer 550, 650, or 750. You'll need the pick ups and igniter if you go that route.

I guess the only thing that makes me think there's still a short somewhere is that the starter button doesn't turn the starter motor. If it was just the Dyna then the starter would still turn over but just not ignite right?

Starter button connects inside of head light bucket, loose?

Yes, the starter should still work, unless something in that circuit got damaged with all the voltage spikes as well. I forget, did you try jumping the posts of the solenoid to engage the starter? If that works but the button doesn't try swapping out the solenoid and see if the button works. If not, disassemble the switch body on the handlebar and see if you can locate a problem with that button. I'm thinking the solenoid might be suspect though.

I did jump the posts on the solenoid. The starter jolts into action.

Its the power to it on the solenoid relay coil that you are missing. Pull the small wire at the solenoid and check for power getting to it when you push the button. Also you can use a test wire to this at the solenoid and it should make the starter spin, if not bad solenoid. No power to it, then probably not to the button, head lamp bucket time.