Author Topic: back to electrical issues again  (Read 5086 times)

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Offline evinrude7

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back to electrical issues again
« on: May 07, 2017, 12:28:45 PM »
went to crank the bike up today and it wouldn't start.  seemed like a low battery.  sure enough i jumped it and now only seeing 13.1 V at 3000 rpm.  my problem seems to be intermittent.  sometimes i get good readings above 14 V but now i'm not.  i can use the bike for a good long while, month or 6 weeks and the battery charges and sometimes this situation comes up.  i've run thru the trouble shooting chart that calj posted in another thread but my lack of knowledge on this stuff leaves me stumped as to what some of the instructions are explaining to do.  i'm sure the POs did some wire hacking here and there but all in all if you look at the wiring it's not completely fuked.  start button missing haven't messed with that.  waiting until i purchase a new right side control and i can start from scratch on that.  i turned the adjustment screw on my aftermarket regulator (there is a stock reg on the bike) and nothing, no changes in voltage while running just below 3000 rpm.  i have both as pictured below.  an aftermarket regulator and the stock rectifier.  can someone explain what i have?  do i have a combo reg/rect in the first pic and stock rectifier in the second pic?  if i have a reg/rect combo in the first pic should i disconnect my stock rectifier?  any help appreciated.  as i mentioned there is another extensive thread i created a while back on this issue but i can't seem to locate it. 

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Offline BomberMann650

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Re: back to electrical issues again
« Reply #1 on: May 07, 2017, 01:34:04 PM »
You have an Oregon Motorcycle Products vreg, which are damn good units.

Your rectifier below that could be suspect.  OMP also makes a damn good replacement.
But first!
Get your multimeter and set it to ohm mode.
Check for resistance between the 3 yellow wires, if ya get a lot of Nuthin'.  Its smoked.

I learned the hard way - the older rectifier do not like high amp charging.  Anything above 10 amps can and will damage them.  The omp units can handle a bit more but still not recommended.

Offline TwoTired

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Re: back to electrical issues again
« Reply #2 on: May 07, 2017, 01:40:03 PM »
went to crank the bike up today and it wouldn't start.  seemed like a low battery.  sure enough i jumped it and now only seeing 13.1 V at 3000 rpm. 

You have to check the charging system with a fully charged, known good battery.  Why? becasue the even a working charging system can't bring the battery back to full power instantaneously.  Takes time for the voltage to rise and determine if the system can maintain the battery.

my problem seems to be intermittent.  sometimes i get good readings above 14 V but now i'm not. 

That could easily be related to the actual charge state of the battery.

i turned the adjustment screw on my aftermarket regulator (there is a stock reg on the bike) and nothing, no changes in voltage while running just below 3000 rpm. 

If you just twiddled the screw to see an effect, it is almost certainly unsuitable for any further use until a competent person adjusts it properly.

can someone explain what i have? 

If the regulator module has only the green wht and black wires, it's not a combo.  And from what you've pictured, the rectifier is still in circuit.

How else is your electrical system different than stock? what lights and other powered devices have you altered?

Have you charged the battery off the bike?
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Offline evinrude7

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Re: back to electrical issues again
« Reply #3 on: May 07, 2017, 01:43:10 PM »
Charging now. Pos and neg still hooked up to bike. Main fuse pulled.

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Offline TwoTired

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Re: back to electrical issues again
« Reply #4 on: May 07, 2017, 01:44:17 PM »
You have an off bike charger?
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Offline evinrude7

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Re: back to electrical issues again
« Reply #5 on: May 07, 2017, 02:18:56 PM »
Charger

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Offline evinrude7

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Re: back to electrical issues again
« Reply #6 on: May 07, 2017, 02:19:38 PM »
Connected to battery. Main fuse removed.

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Offline TwoTired

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Re: back to electrical issues again
« Reply #7 on: May 07, 2017, 04:04:19 PM »
If all were working properly your set up will work fine.  However, the charging system is not fused and the battery connects directly to the rectifier.

Since the rectifier has yet to be tested, it *could * interfere with charging.

What is the battery voltage now?
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Offline evinrude7

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Re: back to electrical issues again
« Reply #8 on: May 07, 2017, 06:15:51 PM »
13.6 V.  it sat for about 4+ hours.

You have an Oregon Motorcycle Products vreg, which are damn good units.

Your rectifier below that could be suspect.  OMP also makes a damn good replacement.
But first!
Get your multimeter and set it to ohm mode.

bomber - i tested the rectifier last time this stuff came up.  it tested fine. 
« Last Edit: May 07, 2017, 06:18:59 PM by evinrude7 »
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Offline TwoTired

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Re: back to electrical issues again
« Reply #9 on: May 07, 2017, 08:08:44 PM »
I Don't know the specs on your charger.  But, an autocharger should bring it to 14.5V -ish, then switch to a float mode, which should hold it at 13.6-13.8 volts.

After you disconnect the battery, measure it again after 2 hours rest, unconnected to anything. S/B 12.6V minimum and new ones can show 12.8V.

That would signify a fully charged battery, ready to begin measuring charging system numbers at idle and in 1000 RPM increments up to 5000 RPM.

Use the kick start, so a not to suck power out of the battery during electric start.  Report the data collected.
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Offline evinrude7

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Re: back to electrical issues again
« Reply #10 on: May 08, 2017, 05:46:35 AM »
i've no start button so not a problem.  will get back to you on this soon.   thanks. 
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Offline evinrude7

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Re: back to electrical issues again
« Reply #11 on: May 09, 2017, 06:33:23 PM »
After you disconnect the battery, measure it again after 2 hours rest, unconnected to anything. S/B 12.6V minimum and new ones can show 12.8V.

That would signify a fully charged battery, ready to begin measuring charging system numbers at idle and in 1000 RPM increments up to 5000 RPM.

Use the kick start, so a not to suck power out of the battery during electric start.  Report the data collected.

TT, i've 12.7 v right now.  can i start the process?  it's from my last charge on sunday.  it had charged 4 hours.  then i kick started the bike and rode it for 20 mins and parked it.  hasn't been started since.  bike has sat, battery cables connected.  i just disconnected them to check the voltage and got 12.7 v. 
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Offline TwoTired

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Re: back to electrical issues again
« Reply #12 on: May 09, 2017, 07:13:59 PM »
12.7V is fine for a charged and rested battery.

Now start it and report the voltage at idle and 1000 RPM increments up to 5000 RPM.
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Offline evinrude7

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Re: back to electrical issues again
« Reply #13 on: May 12, 2017, 04:28:49 PM »
12.7V is fine for a charged and rested battery.

Now start it and report the voltage at idle and 1000 RPM increments up to 5000 RPM.

battery not connected to bike 12.6v
idle 1400 rpm - 12v
2000 - 12.2v
3000 - 16v took a while to get up that high started around 12.2 and slowly rose to 16
4000 - 17v
5000 - 17.1v
6000 - 17.2v

bike idles around 1200 -1400 rpm.  it spits a bit from #3.  need to check float bowl levels.  i think 3 is low.  idle at 1200 or 1400 isn't super smooth but low as i can get it before it wants to cut out.  i did this test a while back and saw 14.4 v around 5000 rpm.  i've never seen 17 v until now. 
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Offline magnum56

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Re: back to electrical issues again
« Reply #14 on: May 12, 2017, 05:00:13 PM »

14 .5 would be about the highest reading you should ever get.

Based on those readings, your voltage regulator is not working correctly.

Continued charging at over 15 volts will basically boil the acid out of the battery.
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Offline TwoTired

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Re: back to electrical issues again
« Reply #15 on: May 12, 2017, 05:03:18 PM »
Either the regulator or the wiring integrity is at fault.  But, your alternator appears healthy.

If you still have the stock regulator, almost certainly the adjuster was tweaked by the clueless.  At that overcharge rate, the electrolyte will go into electrolysis (separating into oxygen and hydrogen, looks like boiling.)  Those gasses are highly flammable and explode in confined spaces, such as inside the battery.
The regulator on this bike is a charging limiter.  It regulates the system indirectly by keeping the battery at full charge.

Spitting back can be too lean, faulty timing, incorrect valve clearance, a burned or bent valve, or poor vacuum sync.
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Offline evinrude7

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Re: back to electrical issues again
« Reply #16 on: May 12, 2017, 05:37:29 PM »
Either the regulator or the wiring integrity is at fault.  But, your alternator appears healthy.

If you still have the stock regulator, almost certainly the adjuster was tweaked by the clueless.  At that overcharge rate, the electrolyte will go into electrolysis (separating into oxygen and hydrogen, looks like boiling.)  Those gasses are highly flammable and explode in confined spaces, such as inside the battery.
The regulator on this bike is a charging limiter.  It regulates the system indirectly by keeping the battery at full charge.

Spitting back can be too lean, faulty timing, incorrect valve clearance, a burned or bent valve, or poor vacuum sync.

14 .5 would be about the highest reading you should ever get.

Based on those readings, your voltage regulator is not working correctly.

Continued charging at over 15 volts will basically boil the acid out of the battery.

as you can see in the photo below i have an aftermarket regulator that is adjustable.  which way do i turn the adjustment screw to lower the voltage?  i assume counter clockwise.  any suggestions on how to perform this adjustment or do you just crank the bike up to 5000 rpm and turn the screw counter clockwise til the voltage comes down to 14.5v?

pretty sure the spitting is low fuel level in float bowls.  plan to attend to that this weekend.  timing is off will fix that as well.  valve clearance is correct.  hopefully not a bent or burnt valve.  vac sync planned after i check the rest out. 
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Offline TwoTired

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Re: back to electrical issues again
« Reply #17 on: May 12, 2017, 08:44:17 PM »
any suggestions on how to perform this adjustment or do you just crank the bike up to 5000 rpm and turn the screw counter clockwise til the voltage comes down to 14.5v?

Yeah, I'd give that a shot.  Or, contact who makes the regulator.   I've never seen that particular one.

Could be tricky since the battery will hold a surcharge without a load on it.

Maybe, turn it way down, start it up, noting the too low voltage.  Then rev it above 2K and bring the voltage up til it hits 14.5 or 14.7.

If you turn it down and the reg still climbs past 14.5V, you may have a shorted regulator.  Again, contact the mfg.

Cheers,
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Offline evinrude7

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Re: back to electrical issues again
« Reply #18 on: May 12, 2017, 09:50:48 PM »
that's a reasonable idea.  i'll work with that until someone says it's not a good one.  seems to make sense that the reg was simply turned up too far.  in addition, i'm sure there are other issues.  for now it's about getting this thing running as solid as it will run as is.  i'll betcha it was me that turned that damn screw too far. 
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Offline Deltarider

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Re: back to electrical issues again
« Reply #19 on: May 12, 2017, 11:31:45 PM »
First I'd repeat the test with an analogue voltmeter. Some DMMs give funny, too high, readings.
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Offline evinrude7

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Re: back to electrical issues again
« Reply #20 on: May 13, 2017, 01:31:06 PM »
this probably sounds like a dumb question but i'll ask any way.  never been afraid to look like an idiot.  other than the ground strap to the frame which i have cleaned the connection, where else on the bike are there grounds that may need cleaning to achieve proper grounding?  headlight bucket, got that one.
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Offline Deltarider

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Re: back to electrical issues again
« Reply #21 on: May 13, 2017, 01:45:30 PM »
Quickest way to find out is in the wiring diagram. Ground is green (like grass is).
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Offline evinrude7

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Re: back to electrical issues again
« Reply #22 on: May 13, 2017, 02:08:28 PM »
my guess is the regulator is bad.  no turn of the adjustment screw makes any change to the voltage at 3000 rpm.  still sits around 16 volts.  how do i test the regulator? 
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Offline evinrude7

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Re: back to electrical issues again
« Reply #23 on: May 13, 2017, 02:44:24 PM »
the guy that made my regulator says follow this...


Quote
#23. Over Charging on bikes with an electromagnet alternator

The problem is usually caused by a bad ignition switch or other connection between the rectifier output and the voltage
regulator power input.

The way it works is the voltage is sensed on the wire that feeds power to the regulator but the power output is on the wire
from the rectifier.  This is usually the main switched power lead but on some bikes have a separate wire from the fuse box to
feed power to the voltage regulator.

These 2 wires connect when the ignition switch is turned on and if the switched power wire has low voltage, the regulator
boost the output until it gets what it's set to produce. 

The way to test this it to with the ignition off unplug the regulator then turn the power on and test the voltage from the
switched power wire to ground.  Any difference in the voltage here from battery voltage will be the amount it over charges.

On Hondas the main switched power lead is black.  Yamaha and Kawasaki use a brown wire for this and Suzuki uses an
orange wire

i'm not understanding what to actually do.  ok disconnect all the wires to the voltage reg.  then connect the pos lead on meter to the black wire that feeds the reg and the neg lead to the ground wire, switch the bike on?  when i do this i get 11.5 with the key switched to on. 
« Last Edit: May 13, 2017, 02:50:41 PM by evinrude7 »
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Offline TwoTired

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Re: back to electrical issues again
« Reply #24 on: May 13, 2017, 03:21:53 PM »
The black wire to regulator has dual function.
One: it supplies power to operate both the regulator and the field coil.
Two: it is the sense line by which the regulator determines when to gate power to the alternator field coil.

What you have to do is determine what voltage the regulator "sees" when the battery is reading any voltage above 14.5v.

If connectors and switch contacts drop or lose voltage routed to the black wire distribution system, the regulator will have a false basis on which to make decisions and overcharge the battery.

However, if the black wire reads over 14.5v, and it still passes that voltage to the white wire, then the regulator isn't doing its job properly.
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