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Discussion Starter · #1 · (Edited)
Oops, left out the technical details the first time I posted.

2001 Superglide FXD, approximately 25,000 miles, carbureted.

First, I was cruising along the highway with a hot blonde on the B-seat, having a great time, when all of a sudden the engine started coughing and backfiring like the timing was all of sudden WAY off. Of course, total loss of power. The engine was really hot. Cruised a mile or so on the shoulder at low speed, but finally engine died. Had to trailer it home.

A few days later, I tried to fire it up, just to see what would happen. Just pushing the starter switch dragged the battery down stone dead. So I ran jumper cables from the car battery, and tried again. Pulled the car battery down too! (Car engine was running).

I thought I might be seized up, but I'm not. Jacked it up, put it in high gear, took out the plugs, and everything turns just fine by hand. I can turn the back wheel by hand and hear the hissing sound from the valves coming out of the spark plug holes.

Took the motorcycle battery out, tried to run from the car battery only. Still pulls it way down.

Do I have something shorting somewhere? It doesn't pull the battery down until I push the starter switch.

Also, if I have a short, is this likely what caused the original problem of the backfiring and timing being way off?

- Henry Higgins
 

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Similar thing happend with me..Stator/rotor fried. That caused the bike to run off battery only till it went dead. Just before going dead the bike was really having problems hitting on 2 cylinders due to voltage being too low. Coasted into a parkin lot. One diff...it wasnt killing batteries like yours. Find whats causin that dead short and my bet the scooter will run just fine with a freshly charged battery.
 

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Pull all of the fuses except what you need. Eliminate as many things as you can. Probably wouldn't hurt to get electrical manual for it. Test stator and rotor. Physically examine wiring. May see something.

I would be reluctant to buy another battery just yet. Try charging your battery, see if you could use it for testing purposes. Might be fine with good charge.
 

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As metioned, check the insulation on the wires at the front of the ENGNE {around the motor mount and frame}. Use a mirror and LOOK for bare wires. I had a regulator/stator replaced, when all that was needed was some tape... :duh?:

Make sure the battery cables are tight and not corroded/broken, up inside the insulation.
 

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Discussion Starter · #7 ·
Progress

I think the stator theory is likely to be it. After deep-charging the battery I got the engine to fire up just fine! That was great. Noticed that the battery voltage continued to drop while the engine was running. That can't be good. Disconnected the stator and the voltage continued to drop at the same rate -- so the stator wasn't generating anything. Next step, I'm going to put the volt meter on the stator while the engine is running. Does anybody know what voltage I would expect to see directly from a good stator?
 

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It might not necessarily be the stator. Power goes from the stator to the voltage reg. first. If your voltage regulator goes bad, same effect. Do a search on checking voltage regulators for test instructions, cause I cant remember the correct voltage readings from the reg off the top of my head
 

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The instruction in the Direct Parts link are not correct as far as checking resistance through the stator. Neighbors 2001 dyna was not charging. Checked stator and had 8 ohms resistance. Spec. in manual was like 4 ohms max. so we DID have continuity...and a bad stator. changed it and he's good to go. Ohm the stator..bet its cooked.
 

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I couldn't find any info on the stator output from the twin cam, but the service manual should tell what it is.... The stator is a pretty heavy duty part. They dont go bad as often as the voltage reg. Check the output from the stator first. If it is fine move on to the volage reg. Before anything check the output wire from the voltage reg. they have a habbit of breaking due to the routing on the 2000-2001 softail models.
 

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henryhiggins said:
I think the stator theory is likely to be it. After deep-charging the battery I got the engine to fire up just fine! That was great. Noticed that the battery voltage continued to drop while the engine was running. That can't be good. Disconnected the stator and the voltage continued to drop at the same rate -- so the stator wasn't generating anything. Next step, I'm going to put the volt meter on the stator while the engine is running. Does anybody know what voltage I would expect to see directly from a good stator?
up to 60V above 2800 rpm
 

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henryhiggins said:
I think the stator theory is likely to be it. After deep-charging the battery I got the engine to fire up just fine! That was great. Noticed that the battery voltage continued to drop while the engine was running. That can't be good. Disconnected the stator and the voltage continued to drop at the same rate -- so the stator wasn't generating anything. Next step, I'm going to put the volt meter on the stator while the engine is running. Does anybody know what voltage I would expect to see directly from a good stator?
re-reading this, Are you refearing to the plug that runs from the stator output hole to the voltage reg. ( you have to be cause you cant just unplug the stator) When you unplug that connection you aren't going to get any voltage to the battery. You need to test the stator at that output hole not the battery. If there is output comming from that hole (within specs) it isn't the stator, check continuity. It is something else. Oh and for future reference dont ever jump your bike with your car! This will definately fry the voltage regulator due to the fact that the auto's voltage system carries an ass load more amperage than your bikes.
 
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