Electrical blues

[chiphead]

So I finished staining the inside of one of my decks and blew off staining the outside 2nd floor part because of a recently disturbed hornets nest. Nice day, seemed like the perfect excuse for a ride.
Dug the 1100 out of the back of the garage and started to warm it up. Noticed that when I revved it, the headlight and neutral light would get dim. Shut if off and went to restart and I had no electrics at all. Digging in I found the main fuse blown. Long story short, after I replaced the main fuse I found if I start the bike and let it idle, all is well. As soon as I rev it over 1.5K the main fuse blows. If I unplug the reg/rectifier from the circuit I can rev it to my hearts content. I've got about 75 VAC coming out of all three phases on the stator and the resistance readings on the regulator/rectifier are on the low side. Looks like my first step is to replace it.
What's the best setup to but one of these? Electrolux? The Honda ones?
Any input would be greatly appreciated.

 

[Jaguarjoe]

For the money its hard to beat Duaneage's Honda R/R kit for $40.

 

[chiphead]

Thanks jaguar.
More bad news. I have 1-2 ohms resistance on 2 of the 3 the stator wires to ground. I don't think that's right. I question why it seems to have excellent AC output though.

 

[SPARKSS]

Thanks jaguar.
More bad news. I have 1-2 ohms resistance on 2 of the 3 the stator wires to ground. I don't think that's right. I question why it seems to have excellent AC output though.

Howdy chip.......you either have low resistance to ground on your 3rd stator wire or you have 2 problems. The stator, by itself is isolated from ground, providing 3 individual sources of AC which are electrically 120 degrees seperate from each other. All windings are connected together in either a Y (Correctly called WYE) or in a triangle (less usual on GS's but called DELTA). With the stator wires disconnected and you should only see voltage between each of the 3 pairs and NO voltage with respect to ground or chassis - this means at least one place in any of the windings has rubbed or burned through to the core. Because your rectifier is designed to utilize a floating winding (it's connection is called a full wave bridge), with a short to ground in the windings, it sees AC voltage only a fraction of what it normally would.

I mentioned 2 problems........assuming one of the wires does NOT show low resistance to ground, this means that one of the windings has burned open (and is likely also the point where the other end of the burnt connection has grounded).

You're needing a stator rewind or replacement.

 

[KGB]

Steve,
Ricks motorcycle electrical is in Plaistow.
Not on rte 108, the "other Ricks"


He does stator and windings for Dennis Kirk by the way.
Nice guy,local and does good stuff.


So you'll be ready for Moosehead right ??

 

[chiphead]

Howdy chip.......you either have low resistance to ground on your 3rd stator wire or you have 2 problems. The stator, by itself is isolated from ground, providing 3 individual sources of AC which are electrically 120 degrees seperate from each other. All windings are connected together in either a Y (Correctly called WYE) or in a triangle (less usual on GS's but called DELTA). With the stator wires disconnected and you should only see voltage between each of the 3 pairs and NO voltage with respect to ground or chassis - this means at least one place in any of the windings has rubbed or burned through to the core. Because your rectifier is designed to utilize a floating winding (it's connection is called a full wave bridge), with a short to ground in the windings, it sees AC voltage only a fraction of what it normally would.

I mentioned 2 problems........assuming one of the wires does NOT show low resistance to ground, this means that one of the windings has burned open (and is likely also the point where the other end of the burnt connection has grounded).

You're needing a stator rewind or replacement.

I think I follow you. Am I correct in assuming I should have infinite resistance to ground on all three phases of the stator?
Although the resistance readings are a tad on the low side on all tests of the rectifier, perhaps I just need a stator.
Thanks Sparkss

 

[chiphead]

Steve,
Ricks motorcycle electrical is in Plaistow.
Not on rte 108, the "other Ricks"


He does stator and windings for Dennis Kirk by the way.
Nice guy,local and does good stuff.


So you'll be ready for Moosehead right ??

I was pretty discouraged yesterday. It's the old "when is enough enough?" Although I love the bike and I absolutely love to ride, it seems I'm dumping $$$$$ and when I'm all done, I still have a rusty crusty 25 year old motorcycle.

My son crashed his car a couple of weeks ago, I've got two kids going back to school and I'm hemorrhaging money. Bah.

Keith, do you have a contact # for this Ricks?

Thanks.

 

[chiphead]

I found the link for Ricks here:
http://www.ricksmotorsportelectrics.com/index.php

Can someone verify that all stator leads should have infinite resistance to ground? I think I'm confusing myself.
Thanks.

 

[SPARKSS]

I think I follow you. Am I correct in assuming I should have infinite resistance to ground on all three phases of the stator?
Although the resistance readings are a tad on the low side on all tests of the rectifier, perhaps I just need a stator.
Thanks Sparkss

You're correct on your assumption regards the stator. I'm not sure how you tested your rectifier OR regulator (mine are seperate units) OR a combination unit but I'd suggest highly that you test a rectifier bridge looking for forward voltage drop (diode test on most digital meters) which should be on the order of .5-.7 volts typically (not zero) and that reverse voltage shows no current (these meters don't test this very well).. A regulator test can be performed with a variable voltage power supply, series resistance and ammeter (assuming basic zener diode shunt regulator).

In practice (stator testing)......resistance to ground will more likely read high megohms.....the real world proof of suitability will be in how well each phase generates and how isolated it is from ground (or it's core)....as previously mentioned.

Regards your post title......nothing quite LIKE the electric blues eh!

 

[chiphead]

You're correct on your assumption regards the stator. I'm not sure how you tested your rectifier OR regulator (mine are seperate units) OR a combination unit but I'd suggest highly that you test a rectifier bridge looking for forward voltage drop (diode test on most digital meters) which should be on the order of .5-.7 volts typically (not zero) and that reverse voltage shows no current (these meters don't test this very well).. A regulator test can be performed with a variable voltage power supply, series resistance and ammeter (assuming basic zener diode shunt regulator).

In practice (stator testing)......resistance to ground will more likely read high megohms.....the real world proof of suitability will be in how well each phase generates and how isolated it is from ground (or it's core)....as previously mentioned.

Regards your post title......nothing quite LIKE the electric blues eh!

OK so the stator is toast.
I tested the reg/rec using the resistance ohm meter methods outlined in the original factory manual and all tests were a couple of ohms less than the values the manual stated. I'm concerned that the symptoms of the main fuse blowing right off idle indicates some sort of a electrical surge being generated by something or the inability of the regulator to do its job. The stator is junk but I'd hate to replace the alternator and find a bad reg/rec fries up the new one. I don't have a digital meter and honestly, some of your testing recommendations are beyond my understanding. I'm almost leaning on spending the extra $100 and just replace the reg/rec. Opinions?
Thanks again sparkss.

 

[SPARKSS]

Well Chip......Digital meters that'll be very useful are cheap now. Regularly I see very useable ones here for $15-20. It does sound like you need a stator. What I'd very much recommend is digging into some basic electrical theory, preferably with some hands on help from someone who understands and has experience. That will be far more value to your understanding and accurate testing and repair. Throwing parts at a problem "may" result in a fix but, without the understanding, you'll never know what fixed it and why or why the parts didn't. Best I can offer without being close enough to help you myself

 

[chiphead]

Point taken.
Thank you.

 

[chiphead]

Just a follow up. New stator from Ricks and a insurance auxiliary ground to the battery and the thing is charging the best it ever did.
Thanks for your help.

 

[tomm]

Hi Chip - Looks like you're all set now, but if the problem comes back I'm probably just up the road from you in Lee. Although I'm not familiar with the specifics of your bike, I've done a ton of work on my own, which is a 78 GS750EC, and I'm an electrical engineer, so this electrical stuff is pretty basic for me. Please don't hesitate to send me a message if you need any more help in that area. Tom

 

[chiphead]

Thanks tomm.
I'm in Chester. I'll keep you in mind for electrical help. Maybe we can hook up for a short jaunt.