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Discussion Starter #1 (Edited)
Hi, I was wondering if anyone is in Michigan that could take a look at my 2003 VN750? I posted about my headlight issue at the end of last year and I did the blue wire mod and I got the light working but it dies from not getting a proper charge and so on. I've had 3 different mechanics check it out and I've done the research on here pretty extensively. I might need to get the Mosfet R/R. I had a guy check the stator and he said it checks out but could be a magnet inside.. I got a new AGM battery.... I would prefer to have the light work with the blue wire in the stock position. Do I just need a new RLU? I'm just exhausted at this point with the trouble shooting. I love the bike and really would just love to take it to someone with some expertise on this bike specifically who I will gladly pay. I am in the Detroit area but I can ride it to anywhere in southeast Michigan. THANK YOU ALL
 

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Need to know the exact results of all the stator tests. If the mechanic thinks it could be a magnet, stator output must not be very good.
 

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Discussion Starter #3
He said the stator tests were fine but he said what he said based on that MAYBE thats the problem. But, I guess not if the stator tests were good. He basically couldnt fully diagnose the problem which seems to be the trend here. Thats why a local expert who's dealt with this problem would be AMAZING. thank you for the info. very much appreciated. He told me to get a new R/R and go from there. I'm pretty sure that after I ordered it from my readings on here that I just replaced a ****ty one with a ****ty one.
 

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That's what I don't get. If the stator tests fine, why would anyone suspect a magnet problem. Low charging volts?

There are specific tests for the stator and RR, you follow each step and at the end you what's good or bad. .... ,instead of loading the parts cannon.

If all truly tests fine, then it's time to check wiring. The bullet connectors on the stator leads and the RR plug are common problem spots.
 

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Discussion Starter #5
Thanks. So say hypothetically I find a problem with those wires... will the headlight work with the blue wire back to stock? I don’t really like how I’ve stacked problems on top of each other even though people swear by the blue wire mod. I get that it’s great, it did get my light working. But I didn’t really have a charging issue until then. Maybe I did but it wasn’t enough to ever kill the bike. If it’s a very minimal charging issue I can live with that and did for quite some time. I hope you get where I’m coming from in this way too long of a rant. I just feel if I can get the light working with the blue wire in stock position like before then I will be fine like I was before.
 

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The blue wire mod should have no effect on the charging.

One leg of the stator is what normally what triggers the headlight relay. If that leg has no output, the headlight stops working.

Need specific numbers on what the stator is actually doing.
 

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Hey Craigconey,
What Spockster said is on the money. The blue wire mod wouldn't CAUSE a drain. It would only exacerbate one if you sat for a long time with the ignition 'on' without the engine running. Once the motor is spinning, the headlight draw is exactly the same.

There should be some threads around on how to check your charging voltage on the DC side of the R/R, as well as the voltage between each pair of the three stator legs. Doing that while the engine is running will give you a good idea of what's generating power, and what isn't.

Wish I were closer.
 

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Discussion Starter #8
The 3 yellow wires coming from the stator go into some big taped up bunch of wires. I don’t see where the plug they go into is. There’s a box with 4 wires. And a box with 2 wires (one solid yellow and one yellow and black. I also found that there is an unplugged R/R under the battery. Mine is mounted on the side behind the cover plate. Please is there anyone from Michigan? I’m dying over here. Thanks. What about that Michigan Teddy Bear guy. Says he’s in Florida. Does you remember anyone from here? Ahhh

Can someone explain how to test the R/R? I keep seeing ways to test the stator. I read a post earlier about a guy saying he was gonna change the stator even though the tests came back good. Everyone was like why would you do that it’s such a pain?” He did it anyway and all his problems were solved. That job no matter what there’s no chance I could do. I would love to take this bike to someone and drop it off.
 

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MTB is still here and still in Florida as far as I know.

The three stator wires running to the wad of tape indicates someone did away with the problem bullet connectors. If not done right, could be a problem spot.

The original RR was abandoned in place and a new one mounted under the left side cover. If it's a MOSFET type RR it will have five wires, three yellow stator wires, one to battery positive, and one ground.

Is the factory RR still plugged in?
 

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The test for the RR is in the repair manual, there is a link in my signature if you're on a computer.

Test is done with an ohm meter between all the terminals. Looking for specific ohms and open/closed circuits.
 

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I am still in Florida, the name Michiganteddybear goes back over 20 years of internet use, if you see that name on a forum someplace, there is a pretty good chance it is (or was) me.

the tests listed in the manual (and those created here) are not perfect. if certain parts of the test fails, its certain that the part under test is bad. you CAN have a R/R test good by the tests, and still be bad. Same goes for the stator (even more so)

as far as stator tests go, some are 'static' (engine off), some are dynamic (engine running) and some tests return different values depending on temp of the stator. it IS known that stators can and do test ok on all the cold tests but fail the hot tests.

the quick basic stator test is:
1. disconnect the yellow wires (3) from the wire harness
2. measure resistance from the 3 yellow wires to chassis/engine ground. ANY reading other than infinite/open circuit means stator is bad.
3. measure resistance between any 2 of the yellow wires, noting the reading. recheck with other 2 combinations of wires. if any of them is significantly different, stator is bad. these resistance measurements are gonna be in range of 2-4 ohms
4. start engine (leave yellow wires disconnected), rev to 2500-3500 RPM, measure voltage between any 2 wires, again noting reading, repeat for other 2 combinations. anything less than 50V AC (this measurement is variable, but it seems like 50-70 is normal) is probably meaning bad stator. this is NOT a check from yellow wire to ground, the current path on this circuit does not go through ground until south of the R/R
5. if everything is ok so far, warm engine fully, and repeat the tests.

it is worth noting that the stock charging system really dont start to charge the battery until 2500+ rpm, so if your putting around town at just over idle pretending its a harley your not gonna charge the battery. Also, the maximum output current of the charging system is quite low (this aint a car with a 100+ amp alternator), so it will take sustained running over 2500 or so to do any real charging of a battery.

aftermarket 'stock' replacement parts are down right crap. if your gonna go with a 'stock' part, get genuine kawasaki ($$). you can get replacements that are an 'upgrade' but they will require modification of the bikes electrical system. The MOSFET regulator is more efficient that the stock one, and with a good stock stator can actually charge at idle speeds. there used to be aftermarket stators that where better, but the supplier of them seems to have vanished, AND they required sending in your bad one as a core (yes, TPE tried to keep some avail so down time was minimal, but they where all still rewinds).

now, all of the above has been typed just as I woke up for the day (I work overnights) so if its got an error or omission, dont shoot me!
 

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Discussion Starter #12
Wow thank you so much. To all of you here I really do appreciate it. However, my brain and time is racked on this one. Is a power sports type place a good idea to take it to? I just really want someone who has worked on this bike before. I’d gladly pay someone. Just seems like all the good folks out there are in this forum which is great and all but.... I need to drop it off with a pro. Much appreciated.
 

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Discussion Starter #13
Need to know the exact results of all the stator tests. If the mechanic thinks it could be a magnet, stator output must not be very good.

So I did the 3 yellow wire from the stator. I removed the plug from the R/R and tested the 3 yellow wires that are all on one side of the box. My multimeter was set to 200 OHMs
1-2= 0.8
1-3 = 0.8
2-3 = 0.8

My new R/R came today and I’m getting the same results. 3,000 RPMs will get me up to 12.9 hit 13 once. Bike off goes down to 12.42 with the radiator fan still blowing. Once it shuts off the bike rested at 12.65. When I went back the bike went up to 12.68 with it off.
 

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Don't have the specs handy, but so far so good, I think.

Need the stator AC voltage output, and the ground test results.

Your battery is doing fine.
 

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Discussion Starter #15
All these tests were with the blue wire back to stock and my headlight not functioning. I put the blue wire back to the mod configuration With the light working and rode around a bit. Now it’s fully rested at 12.53. I’ll check up on the other tests. Thanks
 

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I read about the 2 wire mod. Could that solve my problems.

It's too early to answer that, we don't know if the stator and RR are good.

But generally, yes, the Two Wire mod is good to do as a preventative measure. We just aren't sure if it will help make it charge.
 

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Discussion Starter #18
It started smoking when I tested the 3 yellow wires with the engine at 3k so I **** it off. I saw in another post about testing that part where the guy said “grab your fire suit let’s have some fun” something like that. Not a direct quote. Oooof
 

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Where was the smoke coming from?
 

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Discussion Starter #20
Not positive because my girlfriend was doing the revving and she said it’s smoking so I said shut it off. My eyes were down on my meter. It was somewhere on the opposite side of the bike of the R/R. Is it a bad idea to do it again and tell you exactly where its smoking?
 
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