I have a 96 FLSTC. It got a new battery August 2012 and if it's parked in the garage it's plugged into the trickle charger. It's been running fine all spring so far and today was no exception. Took it out for a 2 hour straight ride with one stop in the middle to fill up. Mostly on the highway running 70-80 just kinda stretching it's legs a little since I've not really gotten to get a good long ride in yet this year after a long winter. Pulled into the garage afterwards, plugged it in to charger, and called my nephew for his bday. He wants me to meet him and his mom for ice cream so I run back unplug the charger and fire up the bike. First try "clunk", second try starts but idle is very low (no tach). I start manuevering it out of the garage and it dies. Try to restart and it winds a couple times trying to start then starts clicking with lights flickering with clicking like dead battery. Turn off aux lights hit starter and it starts, but idling very low runs a couple minutes then dies. Push it into garage and plugged into trickle charger. What should I be looking at (I'm at work now), I'll start with making sure terminals are tight but what else could it be? I can't imagine battery again.

 

checking battery terminal tightness and circuit ground is a good start. Do a search in the evo forum on "stator" and "voltage regulator". You'll find a lot of good information there. It could also be simply a bad battery, but I suspect a stator or voltage regulator problem.

 

Dr.Hess' How To Diagnose Your Charging System



Scale on DC Volts, around 20V max voltage scale. Nominal readings are given in brackets. Check voltage across battery terminals (12.8). Turn bike on. Check voltage (less than previous, ~12.0+,depending on headlight, accessories). Start bike and let idle. Check voltage(could be 12.0 to 15). Rev to about 2500. Check voltage (should be more than observed with bike on but motor not running, and more than with bike off.Ideally between 13 and 15.) Turn high beam on. Should be about the same, giveortake a little. If the voltage is over 15 or 15.5-ish with a headlight on,I'd consider replacing the regulator and/or checking all grounds (battery to frame, regulator to frame in particular). If the battery voltage with theheadlight on, bike not running is less than around 11.5-ish, I’d replace thebattery. If it’s 10, it’s past its prime.

If you pass the above tests, your system is most likely fine, including the regulator and stator. If you don't pass, then:

Bike off. Meter set on Ohms, medium-ish scale, like 20K or 200K Ohms max scale,depending on your meter. Pull stator plug. Ground the meter black lead to a good chassis ground, like a bolt or even the battery negative. With the red lead, touch a different part of the bike, like the engine case at an unpainted part or another bolt. Meter should read low ohms, like 0. If it doesn't, you didn't ground the black lead. With the red lead, touch each contact on the motor side (stator) of the plug (the part stuck in the case). Depending on if your case has a male or female plug, if you can't see the metal part/pin of the plug, you can put a paper clip in the hole and touch the paperclip with your meter red. Meter reading should be infinity on all pins. If it isn't, your stator is shorted to the case, replace.

The following is for single phase systems. I don't have a multi-phase and haven't had to diagnose anyone else’s, so I haven't dug into those systems.

Set meter to lowest ohm scale, like 200 Ohms, typically. (Note: Not 200K ohms).Check resistance between the two stator plug pins. Should be fairly low. My Book says 0.2-0.4 ohms. The spec is in your shop manual. If it is infinity,stator is blown open. If it is 0, stator is shorted to itself.


Set meter to AC Volts, 100V scale. Attach each meter lead to a stator pin. You may need to rig up some type of temporary plug. It is important that nothing can short to ground or to each other accidentally, or you will blow the stator if it wasn't blown before. An old plug off of your last regulator is a good way to do it, but, get creative and be careful. I can do it holding the leads on the pins once the bike is running, but I don't like to. Start bike. Voltage should vary with engine speed. Specs are in your shop manual, but 35V at a couple thousand RPM is probably about right. My book says 19-26 V / 1K RPM.

If you passed that stator test and failed the first test, your regulator is shot. If you failed any part of the stator test, replace both regulator and stator.

 

Sorry about your troubles with your bike, and I'm afraid I won't be of much help to get it fixed. However I can help you if this ever happens again. I posted how to re-wire the key so you can start the bike with the headlights off.

Best of luck, and here is that link: https://www.hdforums.com/forum/evo-c...positions.html

 

I also vote for battery connections. Shine up the terminal and the posts and tighten them down. If it's not at the battery connecting point you may even want to check the other end of the main cables.

Use caution to not short the battery when working on these connections.

I also rewired my ignition switch to be able to start and run the bike without the drain of the lights pulling current away from the starter and ignition. It was very simple and I'll even ride without lights to give the battery a full re-charge on days I'm doing a lot of errand stops and multiple daily restarts.

 

Just went thru this on my 1990 FXRS. I was barely charging and had erratic idling. After going thru the Dr. Hess Test suite, I determined it was the stator. After tearing it down, the stator was in fact fried. I've heard that you can smell a burnt stator by just removing the clutch adjustment cover on the primary (I couldn't smell it on mine).

Follow the Dr. Hess tests and you will find your problem. If it is the stator, I recommend that you also replace all of your inner/outer primary seals, race and bearings while you are doing this. The parts are cheap, but very labor intensive, so since you got the everything apart......

 

Sorry to not get back been busy with work. So I finally just got done doing Dr. Hess charging system test a few times to make sure I was consistant. I failed the first test, but passed everything on the stator so I guess I need a new regulator...fingers crossed that's all. It didn't show more voltage at battery when the rpms were up and as I let it run for a while the readings at the battery both while running and shutdown were slowly dropping. Is that the right conclusion to you guys? I hate electrical on vehicles and coincidentally just had to replace the alternator on my truck last week after it took a dump on me while driving and cost me a tow.

 

After waiting almost 2 weeks for the dealership to get my voltage regulator in I finally got it installed today. Bike is back to charging as it should. You can see in the photo the cracks in the back of the old regulator. I used the testing you guys mentioned above to narrow my problem. Thanks to all that contributed. You guys saved me from just throwing money at everything to fix what ended up being one thing. Of course the past two weeks have been 70's and sunny while waiting for parts, but for the weekend we're looking at rain, and dips into the 50's for highs. Stupid northeastern Ohio. Thanks again.

 

JJ, no need to keep the bike on a battery tender, since your bike doesn`t have an anti theft system that drains the battery. A healthy battery will hold a good charge for an entire winter.

The problem with keeping a bike on a charger is that it can mask a charging system problem, the bike may start fine in the garage because it just came off the charger, but then you get down the road and try to restart the engine after a stop, and then you are stuck.

 

I don't like to disagree with Dan, but I would use a battery tender over winter! Agreed the drain on the battery should be zero, but if your bikes are stored in an unheated garage, as mine are, your battery will reward you with longer service life IMHO. Bikes with kick starters only need a glimmer of battery life to get them going, but a one horse power plus starter needs a hefty kick from the battery to wake up a bike that has sat a few months.