Every time I try to start my bike, the main fuse blows

[lateral4]

I have checked everything I can think of. Here's the situation. My bike just quit running on me today. I checked the main fuse and it had blown. Now every time I replace it and turn the ignition on, it blows out again. Not instantly though. Usually it blows as soon as I kick start it or press the started button. Any suggestions on what this could be? Has anyone run into this problem?

 

[jayel]

what year, stock or modified wiring?

 

[lateral4]

It is a '77 with stock wiring.

 

[sasse]

Could be your voltage regulator, I've seen a few that when they blow, they ground out inside, blow the main fuse.

 

[jayel]

ok checked your other posts so I see you had trouble before that's where to look first maybe have melted some wires there, open the headlight and pull the four wires on the main switch- red (power from battery), light brown (accessory power circuit) red/yellow (ignition circuit) blue (guages) if it blows with no wires to the switch it's somewhere on the red up from battery or rectifier ... plugging in one wire at a time will show which circuit is shorted

 

[jayel]

Could be your voltage regulator, I've seen a few that when they blow, they ground out inside, blow the main fuse.

you are right sasse but it would be the rectifier not the regulator (under the bottom of battery box)

 

[lateral4]

I don't have a connector for the "main" switch. Are you talking about the wires coming from the ignition switch? They each have single connectors on each wire. Should I disconnect all of the wires from the switch except the red wire? I'm not understanding how to troubleshoot the switch. Sorry for the troubles, I'm still learning about the xs.

 

[xjwmx]

You can connect as many as you want from the connector by using pieces of wire twisted around and poked down into.

 

[lateral4]

Ok, I just tested each of the circuits and this is what I've got. It only blows when the red wire, the 12 volt constant" is hooked up. does this mean that my ignition switch is bad? when it is disconnected and I test the wire at the headlight basket I read good voltage from the battery and fuse side. I tested the switch side and here's what I get. When the key is in the off position, I'm getting some resistance from the switch. Once I turn it to the on position, it grounds out, this must be blowing my fuse right? Bad ignition switch? How can I test it to be sure?

 

[xjwmx]

If it blows with only the red wire connected as soon as you turn it to 'on', it does sound like a bad switch of some kind. If you take the switch off you can remove a couple of screws in the bottom of it and get to the circuit board. You can check the connections there and clean it up.

 

[curt698]

That happened to my bike and it was the recifier. In fiddling with it it lost the ground and wasn't isolated anymore.

 

[jayel]

if it blows with red wire connected to switch sounds like switch is shorted internally to ground, the switch can be disassembled and cleaned

 

[lateral4]

Ok, so I took the ignition switch off and took it apart. It's pretty clean, looks brand new actually. I also tested it for continuity and everything checked out the way it should. I guess the next step is checking out this rectifier. Where can I find it and how can I check to see if it's good or not? Thanks for all the advice too guys.

 

[jayel]

if you look at that wiring diagram you will see the red wire from the battery branchs off to the rectifer as it goes up to the main switch, the rectifer is under the battery box unplug its connector if the fuse doesn't blow then, it is shorted... did it blow the fuse with the red disconnected from the switch?

 

[lateral4]

No, it did not blow when the red wire was disconnected. The only time it blows is when I plug in the red wire to the ignition switch at the headlight bucket. I currently have the ignition switch removed and the fuse is perfectly fine. I am also reading 12.68 volts at the red wire at the bucket, so it is strange to me that when I plug in the ignition switch it blows.

 

[jayel]

so it has to be the switch itself .. connect the red to light brown, red/yellow, and blue using jumper wires not the switch .. will it start and run? = bad switch

the sky is falling here in Iowa... first white stuff of the year for my area

 

[lateral4]

I pulled the rectifier completely off and it looks good to me, all of the connections are still intact. There is a little corrosion but no big deal. I will try wiring the jumpers directly and I'll let you know the result. Just a question, I have a broken kill switch, is there any way to bypass it? Can I just wire the two wires from the switch together to complete the circuit ar can I eliminate the switch all together?

 

[xjwmx]

the sky is falling here in Iowa... first white stuff of the year for my area

No snow here, but continuous rain. Since I cleaned up my bike I hesitate to ride in the rain. Best to leave them grubby.

 

[lateral4]

Ok, I jumped all of the wires and I think I may know what the problem is. When I wired the kill switch brown wire, the fuse blew. I think the kill switch is my issue. How can I get rid of it or bypass it or wire it to allow me to start the bike?

 

[jayel]

I pulled the rectifier completely off and it looks good to me, all of the connections are still intact. There is a little corrosion but no big deal. I will try wiring the jumpers directly and I'll let you know the result. Just a question, I have a broken kill switch, is there any way to bypass it? Can I just wire the two wires from the switch together to complete the circuit ar can I eliminate the switch all together?

yes that will bypass the kill switch itself, if it blow the fuse after that you'll have to start tracing the brown circuit wires