81 GS550 electrical issues

[Pchitti]

Having issues with my 81 550. I was riding and the engine started running really rough. Could only keep it running to get it into a gas station. My Neg wire from the battery to ground was smoking. Let it cool down as I grabbed a soda. Tried to start it and battery was dead. Push started it and ran really rough again. decided to leave it till I could get a truck to pick it up. Picked it up that night. Got it home and just left it till morning. Replaced the battery as it was TOAST!!!! battery's + AGM battery less than 2 months old. Got new battery in and tried to fire it up. Would not crank. Checked spark and had no spark on 1&4. Replaced coil with known good coil. Cranked up but only on 2&3. Still no spark on 1&4.

Checked entire wire harness. Its a custom bike so there is only stator, fuse panel, R/R, igniter, pick up. Lights are ran straight from ignition switch. Automotive style ignition switch side mounted.

Since then I have tested the pick ups. They are showing 7.5 ohms each.
Stator looks like it is toast, could not run through stator papers as the bike will not run. Does show 1.2ohms when connecting any of the 3 wires.

Guessing that since my stator is prob toast my R/R is going to be toast also. Anyone have any suggestions for testing other components. I do no have the resources ATM to purchase parts to test. I need to get this back on the road as I just lost my daily driver and bike in the same week....

[BassCliff]

Hi,

Check this page for ignition troubleshooting tips and charging system tips.

*Electrical Odds and Ends*


Thank you for your indulgence,

BassCliff

[tom203]

Sounds like short to me.Strange the fuses didn't blow- are you sure all systems are fused? Anyways, two wires coming out of pickups should have around 300 ohm resistance- if it's like my system- make sure you're reading meter correctly.
Get a new battery charge it up and review wiring. Hard to tell what's at fault. The r/r could have failed causing the charging output to exceed 15 volts . Disconnect charging circuit and figure out why 1 and 4 aren't firing- look for bad connections.

[Pchitti]

Sounds like short to me.Strange the fuses didn't blow- are you sure all systems are fused? Anyways, two wires coming out of pickups should have around 300 ohm resistance- if it's like my system- make sure you're reading meter correctly.
Get a new battery charge it up and review wiring. Hard to tell what's at fault. The r/r could have failed causing the charging output to exceed 15 volts . Disconnect charging circuit and figure out why 1 and 4 aren't firing- look for bad connections.

All systems are fused. Had an issue with blowing the charging system fuse after washing or rain. Other than that had a switch issue which blew 3 headlights before I replaced the switch.

I have checked, cleaned, and repacked all connections. Harness was made less than a year ago, but was not up to standards. Replaced all iffy connections and shrink wrapped with dielectric grease for good measure.

Does anyone have the Ohm measurement from a known good 550 pick-up?