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Discussion Starter #1 (Edited)
Hi. Newbie here. I just bought a Kawasaki Vulcan 700 (1985 - redundant to say, I know), and didn't check further into just what was wrong when the previous owner said that the battery wasn't turning the engine over fast enough to start it so he had to get another battery. I didn't know that alternator problems on bikes, or at least this bike, could be an expensive or time consuming project vs. changing an alternator on a car. I guess that is what I deserved buying an 85 for $1,500 with 17,000 miles on it.

Annie way, I checked the voltage at the battery while still in the bike and turned off and it was 12.5v, and then while idling it is 12.1v. So, yes, I suspected a problem. I've pulled the plug on the regulator/rectifier and tested for resistance across the various 6 posts, and get basically nada on all of them - I have ordered a new regulator/rectifier from regulatorrectifier.com which is supposed to be better than OEM for $100.00.

I also have tested the resistance across the three yellow alternator wires, trying the various combinations of two wires at a time, and get about .18 average. I started the engine and ran it at 4000 rpm and tested across the three wires with different combinations and I only get 17.5 - 19.1 volts a/c. I understand it should be between 50-70 volts.

So, if I did things right, I'm guessing that at least my stator, and possibly the rotor, is shot as well as the regulator/rectifier. Am I right? Or, could I still be missing some things? I've read a number of threads on this group to learn some of this, along with my Clymer manual, but I'm not sure I still might be missing something. Pulling the engine or loosening and tilting the engine sounds like a real pain in the butt, or paying someone else to do it appears to be real expensive. I haven't called yet, but I imagine the labor would probably be somewhere around $500.

Thanks for any help you can give!

chris
 

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Concert connoisseur
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between 600 and 900 is the high and low of having someone do it. there is a walk through in my sig to do it yourself and it is not nearly as hard as it sounds, will cost you about 225.00 and took me about 15-18 hours in two days. I'm sure someone will chime in on your readings first to make sure it is bad before you start. you've came to the right place.
 

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rider
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hi chris.

unfortunately, yes, it does sound like you have a problem with the stator as well. the test you did is a good one... ac volts across two of the three yellow wires coming out of the stator. i think the electrosport fault finding flowchart mentions testing the resistance across the wires, and while i think that's valid, testing the ac volts gets right to the root of the issue. you should be getting 50-70 volts.

i'm a member of the stator changer club. it took two days and i had a friend help. it's not all that difficult, but maneuvering the engine is a little tricky as it's pretty heavy. looks like wib714 has a pretty good writeup... i went by another writeup that i found somewhere (you might want to check the vulcan verses if you haven't already). if i remember correctly, you want to try to leave as many of the wires/hoses/parts connected to the engine as you can to make reassembly a bit easier. you don't have to completely remove the engine... just tilt it out of the bike enough to remove the engine cover.

i like this bike a lot and i intend to keep it for a while, so i spent the money to have the engine cover machined so that if the stator fails again, i'll be able to replace it without taking the engine out. check out http://www.tocmanufacturing.com.

where do you live? add your location to your profile and maybe you'll get a volunteer to help you some weekend.

one last thing. you know the plastic six prong electrical fitting that the r/r plugs into? you might want to consider replacing that if it looks really dirty and worn. i replaced that fitting on my bike (fairly easy process which involves cutting the wires, clamping them into the female electrical fittings, and then clicking those fittings into place in the plastic connector) and noticed a big jump in voltage. you can find the part on electrosport.com under products -> accessories. obviously this isn't going to solve your problem if you have a bad r/r and stator, but it's something to consider.

hope that helps. welcome to the forum.
 

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Discussion Starter #4
Thanks, gentlemen, for the advice. Er, well, at least for the eulogy! :)

It appears that this is a common problem with these. What is the average mileage before the Stator/alternator goes out? Mine only has 17,000 miles on it. If these go out every 15,000 miles then it appears I ought to fix it, drive it for a while, maybe, and then sell it for another - at least another that doesn't require removing the engine just to change out what to me is a maintenance part(s). $800 - 1,200 seems like an expensive price to pay every 15,000 miles to have someone else do it, or 15-18 hours of work. Or, is this happening to most other brands and years of bikes?

Thanks!

chris

p.s. I live in the Phoenix area, having moved here recently from the Dallas area.
 

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Phoenix, we have a problem... Another member, who lives in Phoenix, has replaced his stator 2-3 times. He believes the heat and the lack of adequate cooling for the stator combine to wreck his stators in short order. On his last stator replacement, he rigged up an oil bath for the stator, and has had no more problems. You should be able to view it by searching. Seems lance said his stator and r/r are original to his bike and around 25 years old. So, the answer to your question about how long a stator lasts seems to be: "It depends."
 

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rider
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hey chris.

the vulcan 750 has changed very little during its lifetime, so unfortunately that stator issue is prevalent among all years. the toc manufacturing remachining of the engine cover is $400, i believe, so if you want to go that route any additional stator replacements down the line would pretty much just involve the cost of the stator.

good luck.
 

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Concert connoisseur
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I was at 30,000 and from the looks of it I think it was the original. keeping your oil changed I thinks help a bit. I slacked a little on my changes before mine went, won't do that again. every 3000 filter and all.
 

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Linkmeister Supreme
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Phoenix, we have a problem... Another member, who lives in Phoenix, has replaced his stator 2-3 times. He believes the heat and the lack of adequate cooling for the stator combine to wreck his stators in short order. On his last stator replacement, he rigged up an oil bath for the stator, and has had no more problems. You should be able to view it by searching. Seems lance said his stator and r/r are original to his bike and around 25 years old. So, the answer to your question about how long a stator lasts seems to be: "It depends."
Welcome to our little family here Crisco. Here is a link to the stator cooling mod that flitecontrol mentioned. darrelc5 was in Tuscon 3 years ago when this thread was started. He also has some suggestions and directions for an externally plumbed, stator cooling mod, for anyone who wants to try it. :smiley_th
http://www.vn750.com/forum/showthread.php?t=7306&highlight=stator+cooling

He also has pics of a mod he made by fusing the 3 yellow output wires from the stator. Since then there has been some serious disagreement with doing this mod. IIRC, if the fuse blows, the other two leads have to carry the load and it ends up burning the stator up anyway, which is what you are trying to avoid. I`ll try to find a link that explains this more fully.

Check his pics on flicker, before reading all the directions for his internal cooling mod. It will be easier to visuallize what he suggests, if you do.
He made several posts in June, so he still comes to cruise the forum on occasion, if you want to contact him.
 

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Discussion Starter #9
Thanks, everyone, for your responses. I responded earlier today but for some reason it never posted on the board - guess it went off into the ether. I'll try to respond using the quick reply method and see if it goes through.

I do like the TOC Manufacturing cover method, but it is expensive to purchase and you still have to pull the engine to get to it. I'm thinking about it. It is rolling the dice, however.

One thing I have thought about is a modification of what Harvey Birdman spoke about - cutting the frame, removing and getting the TOC modification, and then instead of placing galvanized pipe with bolts on it (which looks to me would immediately flex and one would possibly have alignment problems) I would find a thicker pipe that would fit snugly inside the frame pipe at each connection and then weld the frame back together along with welding the frame to the pipe inside and thus no flexing of the frame or alignment problem. Then, it would be easy to change the stator.

That, and possibly putting in a cooling system for the stator as well as moving the RR. Hey, here is a question, has anybody ever moved those to some other place than behind the rear passenger foot pegs? Somewhere less noticeable?

Thanks!
 

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Linkmeister Supreme
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On quite a few motorcycles the stock mounting position is right up front, on the lower frame tube, right in the unobstructed air flow. I recall one member contemplating moving his up front, but do not know if he ever did it, or posted any pics.

IMHO, moving it over by the left passenger footpeg is the easiest and least expensive place to relocate it. It has much better air flow than sanwiched between the exhaust power chamber (goats belly) and the battery box. There is marginally less air flow than mounting the r/r at the front of the bike, but you eliminate the possibility of more electrical problems being introduced when you have to fabricate and run a 6 wire extension for the wiring harness.

To my eyes at least, mounting the r/r by the foot peg is not that noticeable or undesireable visually. Coming from under the battery box it may be dirty and stained. A few minutes spent on it with a wire or nylon brush and some soapy water or solvent may clean it up enough to satisfy you. If it is still not up to your standards, give it a couple of light coats of silver colored exhaust header paint. Just my 2 cents worth.
 

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Discussion Starter #11
Thanks, Gordon, for the advice. I've also been thinking of getting rid of the "goat's belly" and letting it cool better that way. Or, forking up the $'s and replacing the exhaust system with V&H pipes.

Does anyone out there have any thoughts about my idea of cutting the frame, removing and replacing the stator, getting the modified cover so I can easily replace the stators in the future, and then using inserts in the frame and welding it all back together? Would that be strong enough and not cause alignment problems that anyone can see?

Thanks!

chris
 

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Thanks, Gordon, for the advice. I've also been thinking of getting rid of the "goat's belly" and letting it cool better that way. Or, forking up the $'s and replacing the exhaust system with V&H pipes.

Does anyone out there have any thoughts about my idea of cutting the frame, removing and replacing the stator, getting the modified cover so I can easily replace the stators in the future, and then using inserts in the frame and welding it all back together? Would that be strong enough and not cause alignment problems that anyone can see?

Thanks!

chris
If the work is done by a certified welder there will be no problem!! :beerchug:
 
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