KrZy8 Gen2 - Charging Circuit

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Well got the R/R harness bypass in from [email protected] Real easy guy to deal with and very quick with email replies and shipping.

So I plug it in to r/r and connect it to battery (front of bike is still all taken apart, ie auxilary 12v outlet, front turn signals disconnected, headlights disconnected.

Bike off (12.8v), bike key switched on (12.6v), started it up and Battery slowly climbed up to 14.02v at idle Awesome! So I connect the headlights and it drops to 12.6/12.7v!?!? Revving the engine to 5000 and it barely moves up at all in voltage.

Can Anyone give me an idea as to why my headlights are drawing that much power? They are Philips H4 55w/60w bulbs, which I believe are the standard bulbs to use.

 
Have you tried to use any other loads, aside from headlights, e.g. heated jacket, etc. which would draw a decent current. Alternately you could let the engine run until the fans kick in to see if the charging system behaves the same way. I suspect it will.

Have you performed the FSM tests on the Stator?

 
Don't despair yet....

Leave the bike on a charger overnight to make SURE the battery's completely charged. Even though you recently put a new battery in it, you haven't been working with a 100% charged battery and your voltage drop from 14.02v to 12.7v when you plug the headlights in could simply be that you're monitoring the "surface" charge. The 14.02v at idle is a terrific sign that the Roadstercycle harness is doing exactly what it's supposed to be doing, but the battery doesn't have enough of a full charge to prevent dropping to 12.7v when you dump a 120watt load on it.

Charge that sucker up completely, then take new readings. That's the only way you can be sure you don't have some other issue, because 14+vdc at idle is "Golden".

 
I did try the heated grips when I had the headlights on and it went from the 12.6/12.7v to 12.5v. Turned the heated grips off and eventually the radiator fan did kick on (with the headlights still connected) and it did the same as well 12.5v. Revved the bike and the Volts come up just a couple .2v -.4v.

I'll have to check the heated grips and fans without the headlights and see what it comes up with.

I did check the stator earlier before I bought the harness bypass and the ohms on the three white wires read equally and checked the voltage when the bike was running and the three wires were all reading around 80v. Stator wires plugged into the R/R testing the R/R output side and it reads around 15v.

I have the battery charging while I'm at work today so I'll check them all again when I get home tonight.

Electrical stuff is not my forte, but reading a bunch on this forum helps out a lot, although I'm still getting stumped. Thanks for the suggestion guys, I'll update when I get more info.

 
I may have missed it somewhere but...........

Where exactly are you measuring 'battery' voltage and what are you using to measure it?

 
Same question as above...where and how are you checking voltage. Is voltage with accessories now lower than before you installed the harness? The voltage output you are reading, if accurate, suggest a stator or R/R failure. The bike is discharging while running, and will sooner than later, not start. I would double check all connections to be sure they are clean and tight. I would give a high probability that one of the battery connections is loose or the stator is possibly grounded.

 
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The voltage output you are reading, if accurate, suggest a stator or R/R failure.
Tom, from what the OP wrote, he was seeing 14.02v at idle after the the harness install...

Well got the R/R harness bypass in from [email protected] Real easy guy to deal with and very quick with email replies and shipping.
So I plug it in to r/r and connect it to battery (front of bike is still all taken apart, ie auxilary 12v outlet, front turn signals disconnected, headlights disconnected.

Bike off (12.8v), bike key switched on (12.6v), started it up and Battery slowly climbed up to 14.02v at idle Awesome!
That pretty much eliminates a stator or R/R problem. 14+v is exactly what he SHOULD be seeing at the battery. The fact that a load is drawing the voltage down immediately indicates either a bad battery, or an improperly charged battery. 12.8v with the bike off definitely points to an under charged battery. It should be more like 13.7-13.9v

Remember, all the troubleshooting in the world isn't going to make up for a bad or under-charged battery. You can't ask for better than 14+v from the charging system at idle.

After villajuan81 gets home today and re-checks a fully charged battery, we'll know more. If the input at the battery terminals is still 14+v, the charging system is good, but if headlights or other loads drop the voltage down to the mid-twelves, then he's got a bad lump-o-lead in the upper cowling, even if he DID just replace it recently, as indicated in his very first post.

 
Sounds to me like there is a high resistance somewhere in the charging circuit. If the RR/stator assembly is capable of putting out 14.0 volts at low load, it should still be capable of putting out 14.0 volts while continuing to supply the loads described above.

The voltage should only drop under extreme loads. If the OP is getting the bike to start there probably isn't a whole lot wrong with the battery. Once the engine is running the charging system should take care of the loads AND recharge the battery IMHO.......

 
The voltage output you are reading, if accurate, suggest a stator or R/R failure.
Tom, from what the OP wrote, he was seeing 14.02v at idle after the the harness install...

Well got the R/R harness bypass in from [email protected] Real easy guy to deal with and very quick with email replies and shipping.
So I plug it in to r/r and connect it to battery (front of bike is still all taken apart, ie auxilary 12v outlet, front turn signals disconnected, headlights disconnected.

Bike off (12.8v), bike key switched on (12.6v), started it up and Battery slowly climbed up to 14.02v at idle Awesome!
That pretty much eliminates a stator or R/R problem. 14+v is exactly what he SHOULD be seeing at the battery. The fact that a load is drawing the voltage down immediately indicates either a bad battery, or an improperly charged battery. 12.8v with the bike off definitely points to an under charged battery. It should be more like 13.7-13.9v

Remember, all the troubleshooting in the world isn't going to make up for a bad or under-charged battery. You can't ask for better than 14+v from the charging system at idle.

After villajuan81 gets home today and re-checks a fully charged battery, we'll know more. If the input at the battery terminals is still 14+v, the charging system is good, but if headlights or other loads drop the voltage down to the mid-twelves, then he's got a bad lump-o-lead in the upper cowling, even if he DID just replace it recently, as indicated in his very first post.
With the bike running, the loads should be coming from the charging system, not the battery reserve. I stand by what I said earlier, I primarily suspect the connections, but with any load, the bike is discharging. The 14 volts at idle isn't much use if he can't even turn on the headlights.

 
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With the bike running, the loads should be coming from the charging system, not the battery reserve.
You're absolutely right, but with a chronically undercharged battery (which it would have been before the "fix") the battery would have been a MAJOR current draw on the R/R's output.

I stand by what I said earlier, I primarily suspect the connections, but with any load, the bike is discharging. The 14 volts at idle isn't much use if he can't even turn on the headlights.
Any discussion, yours OR mine, is completely moot until a fully charged battery is factored in the mix. And apparently, from the first post, the "new" battery is around a month old and the old charging system wiring apparently hasn't been charging the battery worth a flip since new, so based on his readings, the "new" battery is undercharged at 12.6v.

Example -- I very recently had to replace my 11 year old OEM Yuasa. I was starting to get the dreaded "won't hot start" symptom, so every night I put Frankenbike on the charger. Next morning, he'd crank like a brand-new bike, but by the time I got to work, 25 miles/35 minutes later, he wouldn't crank at all. Sit all day, bounce back, and he might crank before the commute home. By the end of the 25 mile/35 minute ride, no crank at all...sit on the charger all night again, rinse and repeat.

I got tired of it one morning and put an external voltage meter on it...14.3v at the terminals with the motor running. Turn the key off and the voltage would drop to 12.2v and continue to drop, one tenth every 20-30 seconds, till it would bottom out around 10.9, NOT enough to re-start. The charge system was putting out plenty...the battery just wasn't taking it.

Put in a fresh AGM, 13.9v static voltage, 14.3v charging.

Until the OP sees 13.5+ on a static voltage read, any further testing will be fairly worthless. So until he reports in, following a complete recharge cycle, we're still chasing undomesticated Anatidae.

Not trying to be an argumentative S.O.B. (although I AM one) but accurate discussion on an FJR charging system requires 2 things to start with...14+v at the battery terminals with the motor running, AND a fully charged battery. The OP's got the 14+v, but we don't know yet if his battery is up to snuff.

 
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JSNS
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Sorry guys, thanks for the replies, i've been really busy with work all week and a friend is visiting from out of town, so i haven't had the time to really dig deeper into my issue as much as i'd like.

Same question as above...where and how are you checking voltage. Is voltage with accessories now lower than before you installed the harness? The voltage output you are reading, if accurate, suggest a stator or R/R failure. The bike is discharging while running, and will sooner than later, not start. I would double check all connections to be sure they are clean and tight. I would give a high probability that one of the battery connections is loose.
I'm checking the voltage right at the battery terminals. The voltage is somewhat better now than before the harness. without the load from the headlights and fan kicking on, i'm getting the 14.1 volts @4-5k rpm. i put the battery on charger for a work day and i'm still getting the same results.

I have all the front fairings off and have pulled apart almost every connection i could get to and put dielectric grease into the connectors. i started to just do the grounding spider connectors, but said what the heck and did just about every connector i could see.

The new (parts unlimited) battery i bought in Hot Springs on July 25th a couple of weekends ago just so i could make it home, which was about a 4 hr ride back, and haven't riden it and have been testing it since. I know i'm missing something here, maybe i didn't test the stator correctly, or i really did get a junk new battery. i was really hoping that the R/R harness was going to be my be all, end all fix; but something else is looming.

Radio Howie, i guess i've never seen a battery with a static charge of 13.5+v, i thought normally its around 12.8v. I guess i need to buy another battery to test it out.

I did notice something weird, that i haven't noticed before, not sure if it's normal… but having the headlights connected and at idle the battery is reading 12.5v, revving the bike it goes up to 12.8v, if i hit the horn button(which i think is an aftermarket-dont see a brand name-but it's a louder low and high tone horn like a car- with a harness and relay) the volts on the battery jump to 13.7-14.xx volts and then back down when i let it go.

Maybe i'll take the stator cover off and look inside if i see any burnt up coils. do i need to have an extra gasket on hand when taking that side off or can it be reused?

Also if theres any techie guys that live near Longview, Tx and would want to take a look at it, i'd be willing to host and buy beer and meals. :)
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Your voltage goes way up when you honk the horn?! Seems like a clue to me. I would explore how that thing is wired in to your bike, especially if it isn't stock.

 
Even though the electrical system is DC there can be a lot of AC noise riding on the DC. This is the electrical system of my FJR at idle; what you see is the noise riding on top of the 14 volts on the positive post at the battery.

FJRVoltage.jpg


Different multimeters will handle the noise in different ways. This noise on a 14 volt DC wire can cause a meter to read 13.7 volts or even 14.4 volts. Some meters are 'slow' and may not see much of the noise and others may see most of the lower frequency noise. Some meters correct for the noise, some average it and it gets added to the DC. Meter specs don't often cover how they respond to noise on a DC system.

The noise on the 'scope has frequencies that shows it's linked to the fuel injectors and the coils. I don't show all the noise frequencies in this one shot.

When horns are honking, the noise is produced by an electromagnet buzzing a diaphragm in the 200 to 600 Hz range -- meaning the electromagnet switches on and off 200 times a second. A high output horn will cause high current AC pulses 200 times a second. Any resistance in the electrical system will cause the current to produce corresponding voltage which = noise on the electrical system. (Technically the voltage will be proportional to the resistance.) The only way the voltage can go up when the horn sounds is electrical noise and a confused multimeter.

I wonder what the electrical system of the 'problem' bikes would look like when checked with a 'scope. It could/might be the problem is noise and the actual battery voltage is good but the multimeter is confused by the noise.

This is one of the few times a needle meter has some benefits. Put a *quality* needle type meter on the electrical system while the engine is running. Put on your best reading glasses or use a magnifying glass and give the needle a hard look. If the needle appears to be 'buzzing' quickly you are seeing electrical noise causing the needle to buzz. In the case of the horn generator you would be seeing serious needle buzzing. Watch out for those buzzed needles
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Now my head hurts. Thanks Ionbeam.
Ya, sorry. As a pilot you know about this stuff
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I don't post this with restraint on purpose. But, sometimes it is relevant enough that it needs to be posted.

Go have a beverage of choice, relax and move on......
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SCOPE SHOWS ALL!!!!

That is an eye opener, Thanks!

Think about what those things are doing when you try to run something without any battery... Shudder....

 
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Even though the electrical system is DC there can be a lot of AC noise riding on the DC. This is the electrical system of my FJR at idle; what you see is the noise riding on top of the 14 volts on the positive post at the battery.
FJRVoltage.jpg


...
What are the scales? Enquiring minds want to know :) .
 
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If you really want to understand what is happening with this circuit you will probably need at least two meters.

One should be hooked up to the DC output from the RR with the other one connected directly to the battery as you have already done.

It will be interesting to see what the results are...............

 
OK, I think I got somewhat of what you were saying ionbeam.

So I pulled up a video about checking the stator and rectifier and there was one test I didn't do, because the SM didn't mention it; I hadn't checked the stator wiring to ground to see if there was any shorts. Setting the multimeter at 200ohm, all the three white wires show a value of 1 when checking to ground. The ohms checking between the three A,B,C phases are equal at .9ohm. The voltage at the white wires all go up to around 80v when revving the engine.... But is all that possible to get the right numbers but it show shorts in all three wires? Or am I just not checking things right?

 
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