Rook32432
XS650 Member
Hello, while I’m new to posting I am a veteran lurker.
I have previously owned a 79 but unfortunately had to sell. I now own a rather troublesome 81.
When I first bought the bike it was completely stock apart from the missing battery box.
The original ignition black box was shot so I fiddled with the gonzo swap, before that too failed.
I opted to swap to the more familiar points setup and run an aftermarket dual coil.
Shortly after getting it running I “simplified” the wiring down to accept a ganged fuse plate. From which I run power to lights and ignition etc. I tested the stock charging system before and after making my changes. I used the tcbros “chopper wiring” diagram as reference. The bike ran well for a few months but I would occasionally get a hiccup in the spark it seemed, so I revisited the points and timing and carbs and wiring and drink and will to live and so on and so forth.
Finally it seemed to run smoothly(as smooth as you would expect). Taken on many 100 miles trips and I trusted it enough that I’d ride almost every day any chance I got. Start up no issue 1-3 kicks(3 on rarer occasion). Advanced well enough for me and would reach speeds of 90+ (I dared not push my luck), you get the gist.
Well about two months ago I was out and about when it began to bog at higher rpm, from 1/2 to full throttle. So I checked my advance and adjusted the springs as they seemed to not be returning consistently , I cleaned the carbs and checked timing etc which all seemed to fix the issue for some time.
Then a few weeks ago the problem came again, this time a complete loss of ignition. I let it rest and I limped it home with erratic spark. Days later I thought of the easy stuff first and cleaned the carbs checked the floats and checked spark replaced the battery and coil. It kicked over as easy as before and ran well as before. Until today..
I rode about 5 miles and the problem began again, i thought “new coil, new battery? Surely the gods would see my hard work with pride and spare me this time..” no, no they did not, the bike kicked one good time only to stumble and die.
Suspecting the coil I tested it and it tested 3.1 ohms on the primary and 15k at the wires without the plug cups. I reattached the cups and tested the secondary again with 30k ohms.
Another puzzling bit is that with the key on I noticed the battery would go from 12.60+ v to 5-7 v. I tested the fuse plate until I found that the wire to the coil seemed to be drawing too much voltage and the battery was draining. I reconnected everything except the wire to the coil and the battery tests at 12+v.
Is it normal for a bad coil to drain a battery, if so why? Is it possible there’s some gremlin hiding in the tubage of my frame causing a bad ground?
So the bike sits, sweaty and silent. Any help at all would be greatly appreciated.
I have previously owned a 79 but unfortunately had to sell. I now own a rather troublesome 81.
When I first bought the bike it was completely stock apart from the missing battery box.
The original ignition black box was shot so I fiddled with the gonzo swap, before that too failed.
I opted to swap to the more familiar points setup and run an aftermarket dual coil.
Shortly after getting it running I “simplified” the wiring down to accept a ganged fuse plate. From which I run power to lights and ignition etc. I tested the stock charging system before and after making my changes. I used the tcbros “chopper wiring” diagram as reference. The bike ran well for a few months but I would occasionally get a hiccup in the spark it seemed, so I revisited the points and timing and carbs and wiring and drink and will to live and so on and so forth.
Finally it seemed to run smoothly(as smooth as you would expect). Taken on many 100 miles trips and I trusted it enough that I’d ride almost every day any chance I got. Start up no issue 1-3 kicks(3 on rarer occasion). Advanced well enough for me and would reach speeds of 90+ (I dared not push my luck), you get the gist.
Well about two months ago I was out and about when it began to bog at higher rpm, from 1/2 to full throttle. So I checked my advance and adjusted the springs as they seemed to not be returning consistently , I cleaned the carbs and checked timing etc which all seemed to fix the issue for some time.
Then a few weeks ago the problem came again, this time a complete loss of ignition. I let it rest and I limped it home with erratic spark. Days later I thought of the easy stuff first and cleaned the carbs checked the floats and checked spark replaced the battery and coil. It kicked over as easy as before and ran well as before. Until today..
I rode about 5 miles and the problem began again, i thought “new coil, new battery? Surely the gods would see my hard work with pride and spare me this time..” no, no they did not, the bike kicked one good time only to stumble and die.
Suspecting the coil I tested it and it tested 3.1 ohms on the primary and 15k at the wires without the plug cups. I reattached the cups and tested the secondary again with 30k ohms.
Another puzzling bit is that with the key on I noticed the battery would go from 12.60+ v to 5-7 v. I tested the fuse plate until I found that the wire to the coil seemed to be drawing too much voltage and the battery was draining. I reconnected everything except the wire to the coil and the battery tests at 12+v.
Is it normal for a bad coil to drain a battery, if so why? Is it possible there’s some gremlin hiding in the tubage of my frame causing a bad ground?
So the bike sits, sweaty and silent. Any help at all would be greatly appreciated.
