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Discussion Starter #1
First off, thanks for all the informational reading I've been doing the last few days. I think I may need to replace the stator in my 94 vn750. Pretty sure the R/R is gone. Before I get too far into this repair I'd like to know if a discharging battery would cause the bike to overheat on a 98 degree day. I'm sure about the temperature because I got to look at the bank sign for three hours waiting for my buddy with a trailer! My thought is that the low voltage may have contributed to the overheating. When the battery was fresh from its overnight tender charge the operating temperature was high but in the normal range. The cooling system is all new except for the impeller and I haven't had problems until the recent hot stretch.

I’ve noticed the bike running hotter lately. A few days ago I had problems starting but it got me home. I checked the old lead acid battery and it was dry. I refilled and charged it, but after some reading decided to replace it with the AGM battery from Advanced Auto. I relocated the R/R and left it on the charger overnight then went on a ride the next day. It ran great for 40 miles then started overheating and not running as well. It stalled at a stop light and was done. Luckily it started and ran long enough to drive it on the tilt trailer three hours later.

When I got it home the voltage was about 10.4. I charged it overnight to 12.5V. I started it and brought it up to temperature, then ran some of the tests in the Kawasaki manual. The R/R Output voltage was only 13V @ 4000RPM, 12V @ idle. I don’t have a meter that can measure 20 amps DC in series so I skipped that test.

The stator coil resistance between leads is 2.2, 1.3, and 1.3 ohms (corrected for lead resistance). They call for .34 to .52 but that seems like a tight range for a set of windings to me. The stator coil insulation test showed infinity from ground to all the leads. I don't want to change this beast if I don't need to. Would much rather be riding.

Testing on the R/R was interesting. The harness connector has been very hot; it is burnt and brittle. The R/R connection looks similar. The B pin has 1.6 ohms to A1, A2, and A3 where it should be infinity. Actually, the only readings that look good are the A1/A2/A3 to each other. Figure its junk.

In a nutshell:
1. Do I have a separate cooling issue? This system was cleaned and flushed a few months ago. Radiator serviced at a shop, all new rubber, no leaks, and new thermostat. It has been running OK till recently.

2. Do I replace the stator or do some more testing? Replacing looks like a PITA. Should I test the AC output? And if the stator is marginal can I install a new R/R and get by until winter?

3. Which R/R to install? My harness side plug is burnt but usable. I like the simple concept of the MOSFET type. The ElectroSport unit gets good reviews and is much cheaper than the OEM one. Whatever I get may have to live with a marginal stator for a while.

Thanks in advance for your support. I don't mind getting my hands dirty but when you're up to your neck with alligators.... This is a 94 VN750 with 39000 miles.
 

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First off, thanks for all the informational reading I've been doing the last few days. I think I may need to replace the stator in my 94 vn750. Pretty sure the R/R is gone. Before I get too far into this repair I'd like to know if a discharging battery would cause the bike to overheat on a 98 degree day. I'm sure about the temperature because I got to look at the bank sign for three hours waiting for my buddy with a trailer! My thought is that the low voltage may have contributed to the overheating. When the battery was fresh from its overnight tender charge the operating temperature was high but in the normal range. The cooling system is all new except for the impeller and I haven't had problems until the recent hot stretch.

I’ve noticed the bike running hotter lately. A few days ago I had problems starting but it got me home. I checked the old lead acid battery and it was dry. I refilled and charged it, but after some reading decided to replace it with the AGM battery from Advanced Auto. I relocated the R/R and left it on the charger overnight then went on a ride the next day. It ran great for 40 miles then started overheating and not running as well. It stalled at a stop light and was done. Luckily it started and ran long enough to drive it on the tilt trailer three hours later.

When I got it home the voltage was about 10.4. I charged it overnight to 12.5V. I started it and brought it up to temperature, then ran some of the tests in the Kawasaki manual. The R/R Output voltage was only 13V @ 4000RPM, 12V @ idle. I don’t have a meter that can measure 20 amps DC in series so I skipped that test.

The stator coil resistance between leads is 2.2, 1.3, and 1.3 ohms (corrected for lead resistance). They call for .34 to .52 but that seems like a tight range for a set of windings to me. The stator coil insulation test showed infinity from ground to all the leads. I don't want to change this beast if I don't need to. Would much rather be riding.

Testing on the R/R was interesting. The harness connector has been very hot; it is burnt and brittle. The R/R connection looks similar. The B pin has 1.6 ohms to A1, A2, and A3 where it should be infinity. Actually, the only readings that look good are the A1/A2/A3 to each other. Figure its junk.

In a nutshell:
1. Do I have a separate cooling issue? This system was cleaned and flushed a few months ago. Radiator serviced at a shop, all new rubber, no leaks, and new thermostat. It has been running OK till recently.

2. Do I replace the stator or do some more testing? Replacing looks like a PITA. Should I test the AC output? And if the stator is marginal can I install a new R/R and get by until winter?

3. Which R/R to install? My harness side plug is burnt but usable. I like the simple concept of the MOSFET type. The ElectroSport unit gets good reviews and is much cheaper than the OEM one. Whatever I get may have to live with a marginal stator for a while.

Thanks in advance for your support. I don't mind getting my hands dirty but when you're up to your neck with alligators.... This is a 94 VN750 with 39000 miles.
you need to do one more test on your stator ,if i didn't miss anything.

Set your meter to ac voltage probably 200 V scale,and test for voltage across all combinations of stator output leads,you should get a reading of 40 to 70 VAC between any and all combinations ie:AI to A2,A1 to A3 and A2 to A3 with the engine running 2500rpm or better.If in spec on all combos your stator is good ,also after doing this test retest for any lead grounded to the engine case with the engine warm.

If you have to but an R/R ,go for the mosfet kit ,I personally believe it is the single best charging upgrade you can do and is worth waiting for another payday or two to buy if you have to, I hope this helps.

On the overheating issue i would wait till the bike is running at full voltage,before I passed judgement on the temp gauge.It works of of a resistor type sending unit and voltage and resistance variances on either of the two could cause false readings,
 

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Old Truck Junkie
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I recommend that you disconnect the bullet connectors and run your test at those wire direct from the stator.
 

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I recommend that you disconnect the bullet connectors and run your test at those wire direct from the stator.
absolutely X2 thanks nite for pointing that out:smiley_th
 

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Discussion Starter #5
I did the stator tests when it was warmed up. AC voltage between leads is 18, 18 and 16 at 4000 RPM. 8 volts at idle so I assume the 12 VDC reading I got earlier was battery voltage.

So it looks like a stator replacement. The ElectroSport one seems to be the only aftermarket one available. The big question is, do you think I can install a new R/R and put off the stator replacement till winter? Its about the riding time.
 

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Discussion Starter #6
A little more research when I should be hitting the hay. I see three stators that catch my eye. ElectroSport, Ricks, and Accel. Any votes of confidence in the Accel? The Ricks one isn't much less than OEM.
 

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I did the stator tests when it was warmed up. AC voltage between leads is 18, 18 and 16 at 4000 RPM. 8 volts at idle so I assume the 12 VDC reading I got earlier was battery voltage.

So it looks like a stator replacement. The ElectroSport one seems to be the only aftermarket one available. The big question is, do you think I can install a new R/R and put off the stator replacement till winter? Its about the riding time.
I'd say you are asking to get stranded with voltages that low,how much difference is there between the ricks and oem,if not much i would go oem or contact Tim Parrot at TPE about having yours rewound,he uses heavier gauge wire and puts out a much better product than even oem. I also would post under thesell or swap catrgory and see if anyone on here has one for sale also check Pinwall cycles on Ebay.Thet are a bike salvage Co. in OH and post everything as buy it now rather than bidding and list mileage of the donor bike.
 

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Giggity!
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I used Tim for my last stator & was VERY pleased. You simply send him yours & he sends you one he's already done. At least that's how it worked when I did it. If I remember correctly, he even gives you credit for yours.

2x on the better than oem. Just remember, you get what you pay for & I wouldn't suggest used unless your on a tight budget. Been there, done that.

Link, Click Me. Tim Parrot Enterprises
 

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Discussion Starter #9
I've got an email out to Tim. The OEM turns out to be over three bills! Real interested in Accel because they have a great reputation in automotive ignitions but don't see much in the way of customer reviews. Got the garage cleaned out and need to start ordering parts soon. Thanks for your help folks. Will keep you posted.
 

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Discussion Starter #10
checking in

The stator is in a box, being shipped to Tim tomorrow. A MOSFET conversion kit is on its way also. I have a few questions after taking her apart I'm hoping I can get some help with.

I noticed the headlight didn't come on when I started it with the R/R disconnected. Am I safe in assuming I will need to alter wiring with the new R/R, maybe jumper something?

I didn't take the bevel gear case off as I wasn't removing the engine. Did I miss something completely? I have an unopened tube of Moly 60 on my bench. I will use it to lube the splines with but I don't see a need to even bring the gear case gasket home. Just pay my restock fee and be done.

Where am I needing silicone gasket compound at? Maybe the stator cover and grommet, but I would think the o-ring will be fine.

One of the cover mounting bolts near the top has a red sealant or thread locker on it. Does anyone have insight on that?

And which bolts, if any, need thread locker or anti-seize? Thinking anti-seize on the exhaust bolts. What needs low strength blue and what needs high strength red?

Neighbor had an extra floor jack which was really handy having two to work with. Once I remembered to remove the coolant tubes out of the heads it came out pretty easy. Big pry bar from HF came in handy. Just waiting on parts now.
 

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Discussion Starter #11
Won't fire

Its pretty much back together except for the covers. Won't start or even fire. Everything looks good, all connections look like they're made, and it turns over good. I'm going to search around but if anyone can point me to a thread regarding this it would be nice. I replaced the Stator and R/R. Added a voltmeter and highway bar.
 

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Just replaced my stator as well. Engine is back in the bike, and will be attaching the cooling and exhaust systems today. After some fresh oil and coolant, I'm hoping to take her for a ride today. Cross your fingers.

--FA
 

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Discussion Starter #13
Running!

Took her for the first ride last night. Old spark plug wires had gone bad. Figure they were burnt inside and moving them around finished them.

Had a considerable oil leak at the stator plug that took a lot of Permatex Ultra black to stop. In hindsight I should have sealed the devil out of it on the inside, but I figured it was a new plug should be fine - WRONG. I'm hoping my patch job holds till winter, Not looking forward to pulling the motor again.

While it was apart I added a set of OEM highway bars for a place to mount pegs. Switched to Rotella T oil and was absolutely amazed how much better the shifting was than with Yamalube. The bike runs really well, the best since I've owner her.

Next issue is cooling. Still seems to heat up a long way and the fan didn't run when I stopped it. Troubleshooting points to the ground or switch.

Thanks for the guidance:smiley_th. I wouldn't have been able to do this job without it. For those thinking about it, it can be done. You will lose some riding time but gain a much better understanding of your machine.
 
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