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Discussion Starter #1
Hi all,

Im the new guy here and am having the same electrical problems as others. My battery keeps running down. When I charge the battery it goes to 13.4 volts then rests at 13.2 volts.

The battery is a new gel battery and holds the charge.

When I run the bike it performs great... its' just that I seem to be using (running) off the battery and not making up the charge through the charging system.

I have done a few tests and will share them with you.

I did the stator test and got these results:
Ohm test: a1 = 0 a1 to a2 = 0
a2 = 0 a1 to a3 = 0
a3 = 0 a2 to a3 = 0

volts ac.

At 2500 rpm the voltage was
a1 to a2 = 41.7
a1 to a3 = 44
a2 to a3 = 44

I then reconnected the r/r and measured the voltage out of the r/r. It was 14.7 volts at 2500rpm.
Then I checked across the battery and got only 12.6 volts.
I then pulled the 2 light fuses and got 14.08 volts across the battery.
I don't know what to do from here. Any suggestions on what to look at next? I have moved the r/r and done thee blue wire mod.

Thanks again.
Dave
 

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Discussion Starter #3
Thanks. I will do that and report back. Can I solder the bullet connectors after cleaning them?
 

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Ohm test: a1 = 0 a1 to a2 = 0
a2 = 0 a1 to a3 = 0
a3 = 0 a2 to a3 = 0
This doesn't look right. Shouldn't it have a lot higher ohm readings?

The output at the r/r is great, so it seems to point to voltage loss at the JB, grounds, or JB/RR plugs. ??

Seems like your stator charges at least some of the time, but some only fail when the engine is hot. And there's also the stator leads to ground test, which should be OL or no connection to ground.

Two-wire mod could help, but I wouldn't tear into that just yet.
 

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Discussion Starter #5
Thanks for the reply. I will check the stator to ground readings and get back to the forum. I will also check the voltage of the white power wiring leaving the r/r and the voltage at the white/red wire coming out of the jb. Thanks again.
 

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Discussion Starter #6
just a quick update. I fried the r/r aand have ordered a new one from rick's. still working the connectors and grounds. have a week to finish this as the r/r won't be here until next Friday.
 

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Discussion Starter #7
Hi all,
The r/r has arrived. Before I put it in and test the charging system, I have another question. When I check the continuity of the stator wires to ground my meter sounds but reads 0 ohms. When I test the resistance between stator leads I'm at about .5. Within specs and the voltage is at 50 plus. Is this looking to you like the stator is good? Thanks.
 

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Hi all,
The r/r has arrived. Before I put it in and test the charging system, I have another question. When I check the continuity of the stator wires to ground my meter sounds but reads 0 ohms. When I test the resistance between stator leads I'm at about .5. Within specs and the voltage is at 50 plus. Is this looking to you like the stator is good? Thanks.
What does your meter show if you connect from battery negative post to the engine block? What does it do with both meter leads touching together?

Your meter giving the sound is what I'm concerned about. That normally means there's a connection. There should be no connnection between the stator windings and ground.
 

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Discussion Starter #9
The meter reacts the same 0 reading and tone. Someone said that a tone might be okay if the meter is sensitive, but I'm thinking the stator may be bad. It is producing enough ac volts but I am only getting 12.6 to 12.8 across the battery. If I remove the headlight and taillight fuses in the junction box all voltages trend upward toward 14+ volts. I am so confused. By the way, thanks for the help.
 

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Well, if I haven't gotten confused myself, it looks like the stator is shorted to ground. But I don't see how you could get any of those voltage readings with a shorted stator.

Can you borrow another meter?
 

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Discussion Starter #13
I purchased an auto ranging meter today and tested the stator.
Bike off and running the same results.
A. stator leads to case
a 0 ohms from case to lead
b 0 ohms from case to lead
c 0 ohms from case to lead

B. Resistance between leads
ab .5 ohms
ac .5 ohms
bc .5 ohms

Bike Running: 3000rpm
AC voltage
ab 55 vac
ac 55 vac
bc 55 vac
 

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I purchased an auto ranging meter today and tested the stator.
Bike off and running the same results.
A. stator leads to case
a 0 ohms from case to lead
b 0 ohms from case to lead
c 0 ohms from case to lead

B. Resistance between leads
ab .5 ohms
ac .5 ohms
bc .5 ohms

Bike Running: 3000rpm
AC voltage
ab 55 vac
ac 55 vac
bc 55 vac
You're good. The tone with the other meter threw me off.
 

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Discussion Starter #15
I am really frustrated. I know so little about electricity as it relates to the bike. The stator tests good. I can't get the r/r to test like the book illustrates, however I can get the diode test to work fine and consistant. I have installed a new plug to the r/r, cleaned and soldered the bullet connectors cleaned grounds where I have found them. The best voltage at the battery I can get is 12.8. I can get 13.8 at the r/r at 5,000rpm. I need to rerun the voltage test removing the fuses for the lights again and double check my results there. Will let you know what is happening. And thanks for all your help.
 

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sounds like you might be losing charging voltage in the junction box, which is a somewhat common problem on these bikes. you may benefit from the upgrade to a MOSFET or Series style R/R. 13.8 at the R/R is OK, but I remember getting up to 14.5 on mine before I upgraded to the Mosfet (not necessary, but I did it anyway)

There's several guides on the upgrade on this website, and couple of places to buy kits to do it. roadstercycle has some DIY kits with everything you'd need, I built my own with an R/R off ebay and got the parts separately. I think I saved a few bucks that way, I can dig into my post history and dig out the details of the parts I used if you have any questions.
 

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Yep, that damn JB. There's three relays in there that usually cause problems.

Headlight relay - Blue Wire mod bypasses that.

Start relay - Two Wire mod bypasses that.

Fan relay - Standalone relay bypasses that.

If I had to pick one to try first, I'd say Blue Wire Mod, and it's the easiest.

Give your r/r wiring a really close look. Make sure the contacts in the r/r plug are clean.

Doing the MOSFET r/r bypasses the OEM r/r wiring, and is really simple to wire up.(positive - negative - stator) Series type may do the same, not sure. I used the Roadstercycle kit.
 

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Discussion Starter #18
Thanks for all the advice. I did the blue wire mod to no avail. It works but no change in charging voltage. I rewired the r/r plug and soldered the new connections. No change. I just put the new r/r on the bike after checking the diodes. Pulled the headlight fuse and the dc voltage at the r/r at 2200rpm was 14.2. Across the battery voltage was at 13.3 or 13.4. I was under the assumption that the voltage coming out of the r/r was not influenced by anything and then at the jb voltage is affected. How is the voltage pulled at the r/r? Is this indicating the jb is shot?
 

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Are there any aftermarket or extra lights on the bike? All the lights are the usual brightness and functioning ok?

You're still getting 12.8v when the lights are connected?

The JB on this bike is a piece of cursed engineering, all are shot, it's the degree of "shot" that varies. The r/r controls voltage, but a short in the JB or anywhere else pulls the voltage down beyond recovery.

I get the impression that you can handle doing the two-wire mod. I'm just not sure if it will fix the problem, it's worth a shot I guess.
 

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Discussion Starter #20
I'll give the 2 wire mod a go and see what happens. I can always put it back if need be. Thanks for your help. I just don't know where to go from here.
 
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