I have a 1996 Sportster 1200. For a while now I've been noticing that the right turn signal INDICATOR does not always come on, although the turn signal does. Then more recently the backlight on the speedometer/odometer would come on, but the speedometer and odometer would take a while to come on.
Monday I went for a ride and parked the bike. I went back to the bike a couple of hours later and went to start it. The odometer and backlight came on, but the headlight didn't, the neutral indicator didn't, the oil indicator didn't, and the start button didn't do anything. I tried the turn signals, and they worked, but the indicator lights didn't. I roughly turned the key off and on repeatedly while wiggling every wire behind the headlight. I'm not sure what I did, but the headlight and oil and neutral indicators came on. I pushed the start button and it started right up. I rode it directly to the shop, where it's been sitting for 4 days now. The mechanic has been starting it every couple of hours to see if it will do the same thing again, but so far it hasn't.
Does anybody have any informed idea of what might be the issue?

I'm sure that I don't have to tell you it could be anything. You need to start someplace and wiring problems on a bike can be difficult to find. I would start with the ignition switch. Make sure that it is ok since you already said that you worked it until you could get it started.

I had a problem with my ignition switch it got a lot of water in it and would not make contact. I squirted some wd40 in it and it started to work fine. When you get it back from the shop if they have not found out what was wrong check for broken or loose wires, burned out bulbs can also be the problem.

Hope this helps, keep us posted on what you find.

Informed??? I can guess, so just going by what you wrote, the loose connection was probably in the wiring behind the headlight, and if it happens again that would be the first place to look.

I appreciate the replies. With the advice of the shop mechanic and the responses here, I've decided to take a logical and methodical approach to solving the problem. I'm going to ride the bike until it acts up again, then NOT try to get it started until going over every wire with a voltage meter.