After posting this in the softail and electronics sections, I think this might be the better place for it. Those other forums are full of EFI bike owners.

OK. My tail light is working. The bike is a 1986 FXST. I just got it a couple weeks ago. No turn signals or horn on the bike. Thus, no inspection. But it's the brake light that keeps me from riding it on the main roads. The wiring block under the seat had some wires that seemed to be in the worng place according to the Clymer book. And the rear brake switch had a loose wire. I fixed what I saw and still no brake light.

Any ideas? Should I just buy a new switch?? Maybe a new wiring block? Maybe just re wire the entire bike? I am learning as I go here and never worked on a bike before now. But I am mechanically inclined and can do it if pointed in the right direction.

Thanks!

Another thing is the gas tank is leaking from the petcock. But I think it is the nipple coming out of the tank. Any ideas how to fix this? Probably gonna buy a new tank anyway but it would be nice to ride what I have until I get the new tank. I have tried the gas tank repair and a tube of liquid metal with no help. It leaks worse when the bike is running or gets hot. It stops after the bike cools down and it sitting still.

 

It will be easier to troubleshoot your electrical problem now and any in the future if you get/have a volt/ohm meter. Radio shack and Harbor Freight have cheapo models for, I believe , under ten bucks. If you spend more, you will get more accurate readings but the cheap ones will do for most stuff. Test your brake switch with the ohm function of the meter to see if it opens and closes properly. With the voltage function of the meter, you should be able to trace through the system by checking at different points along the way from the battery, to the brake light fixture, to discover where the voltage drops, and hence, where the problem lies. Your wiring diagram will help you find the spots where you should test with the meter.
As far as your gas tank, if the nipple off the tank is leaking, it may be cheaper and less hassle in the long run to toss the tank and get your new one now (if ya got the bucks) rather than pull the tank, clean it and go through the internal sealing process. You should seal the new tank before you put it in service as well. Seal it before you paint it. I used Kreem sealer but I see that others on this forum have used another brand that is less likely to fail over time. I don't remember the name of the other stuff. If you do a search for gas tank sealing you should come across the name. I would not be comfortable riding (or even starting) the bike with ANY kind of gas leak.
Good luck.

 

Thanks. Yeah, I think the switch is bad. Gonna get a new one. Gonna go ahead and get a tank too. I just wanted more time to figure out what tank I wanted before buying one.
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I finally found the page in the Clymer book that deals with testing the switch. And it failed. So I hope that's the problem. Also figured out that I don't have a switch on the handle bars as desribed in the book. But the previous owner put drag bars on the bike. It looks like he didn't mess with the turn signals, horn, and brake switch when he did that.

 

I have an electronic copy of the schematic if you want it. I can email it to you.&nbsp\\;

 

I have the Clymer book. If what you have is different, then I'll take it. codysmith1975@yahoo.com
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I replaced the rear switch. Also re wired the socket. The red wire seemed broken. Still doesn't work. Does this year model have curcuit breakers? I haven't checked those and I'm not certain the brake light would be wired into them anyway.

 

I have had similar brakelight problems over the years.....
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The speedometer light, brakelights, and turn signals would not work....I would replace the fuse. The fuse would blow almost immediatley. The real problem would be the headlight connector.
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Somehow, the headlight connector would develop a short in it.....replaced it and no more problems.

 

I sent you the pic.

The accessory breaker feeds 12 volts to group 3 on the junction block (orange wires). An orange wire goes to each brake switch and a red wire returns from each back to group 9. A red wire goes to the brake lamp from group 9. Check for 12 volts at group 3 with the switch on ignition or accessory. Check for 12 volts at group 9 when either brake is pressed.[/align] &nbsp\\;[/align] Rob[/align]

 

Thanks Rob. I'll check it out. For the other poster, I don't think this bike has fuses. I could be wrong but I haven't seen any. It uses the breakers but I don't see a "reset" on them as described in the book. I'm assuming that the breakers are whats located under the ignition switch, between the tanks.

 

Rob, would it matter that the front switch is not connected? Should I unplug the wires from the junction box if they are not connected to the front switch? There's no front switch installed on this bike. It's missing. I guess they didn't reconnect it when they added the drag bars. I'm just trying to get the back&nbsp\\;brake light&nbsp\\;working for now.

 

I've currently got the speedo disconnected and the ignition switch/center consol unbolted so I could see the breakers but no wires are disconnect. I don't have any volts at the orange wires with the ignition turned on. Headlight came on but no volts at&nbsp\\;group 3. And&nbsp\\;no volts&nbsp\\;at red&nbsp\\;wires when I press the brake pedal.&nbsp\\;