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battery not charging

leo750k

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Discovered today that my battery is not charging, I have a manual, and haven't started going thru the list yet,
was wondering if anybody had any advice on what to start with first? I was thinking maybe the brushes on the stater coil?
thanks for any advice
 
One of the most common early DOHC fails...............the rotors. They can check as good and still be bad too. Lots of trouble with the rebuilt ones too. The stator and brushes are relatively reliable unless brushes are simply worn out. The rotor going out commonly ruins the regulator too.
 
Thinking the spec is 4.4 ohm or something like it. Lower resistance is often a good thing but there it is a BAD thing. Shows the layers of wire are shorted and what they do. Many of the ebay ones are bad too FYI.
 
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Here we go................service manual spec. 3.6-4.4 ohm. Nothing outside of that number and they can be bad inside the range there too.
 
Have you known of anybody that has successfully rewound one of these coils themselves? doesn't seem that it would be too hard, IF you knew the wire dia,and number of wingdings. I have a good friend that is a chemist in the semi-conductor industry, he could spec. the potting compound for me.
 
It's harder than you think, the wire coating glue (an epoxy) down job has to be done through the entire wind, surface of the outside only is nowhere near enough. You need a winding machine unless you wind the core and then mount it on the two split halves of the rotor and then you are faced with whether that went back together tight enough. Try winding a core with all the moving in and out to avoid the touching of the rotor wings which with one scratch through the paint insulation scraps the whole job and you'll know why they need a machine to do it or wind the core separate and then you have to make sure it also mounts in tightly enough and glues down well enough the inertia of running never tears the core loose from the rotor iron. Then it needs balancing there at 10,000 rpm and where to do that? The choice of the paint coating on the wire can kill you by itself.

Now you see why the rebuilders themselves have such utter fits getting them right and they DO have fits, and many still go bad very quickly anyway. Even Honda could not make them last. I lost my first one at 3000 miles.
 
It's harder than you think, the wire coating glue (an epoxy) down job has to be done through the entire wind, surface of the outside only is nowhere near enough. You need a winding machine unless you wind the core and then mount it on the two split halves of the rotor and then you are faced with whether that went back together tight enough. Try winding a core with all the moving in and out to avoid the touching of the rotor wings which with one scratch through the paint insulation scraps the whole job and you'll know why they need a machine to do it or wind the core separate and then you have to make sure it also mounts in tightly enough and glues down well enough the inertia of running never tears the core loose from the rotor iron. Then it needs balancing there at 10,000 rpm and where to do that? The choice of the paint coating on the wire can kill you by itself.

Now you see why the rebuilders themselves have such utter fits getting them right and they DO have fits, and many still go bad very quickly anyway. Even Honda could not make them last. I lost my first one at 3000 miles.

"whether you think you can, or whether you think you cant, Your are Right"
but I dont have any way to balance it, so that is a deal killer. thanks for your input
 
I purchased an Electrosport Industries rotor from Parts Giant, it is testing at about 5.5 ohm. battery is still not charging, I have a voltage reg on its way, stater coil is testing fine, and even though the battery is not getting charged, since I installed the rotor the motor now cranks, starts, and runs better then it ever has. Regulator will be here Monday, in the mean time I have been thoroughly cleaning all my connector contacts/pins, and have the battery charging at about 2-3 amps.
Any thoughts or suggestions on the rotor?
And thanks for all the time and effort you have taken, helping me with this project. This week I am going to put together some pics showing what I started with, and where I am now. I have learned a lot in the last 8 months, and will try to pass it on to others, as others have done for me
Sincerely,
Leonard S. Cocoa Fl "success is 10% inspiration,and 90% perspiration"
 
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Battery if new MUST be fully charged BEFORE you ever try to use it on the bike or it will appear to not be charging. Using the charging system to charge up a new battery up is one of the best ways to fail a charging system there is. Been there so many times I cannot count, people seem to insist on doing it.

IF you are going about things that way of course.

Not unusual to have supposed 'new' rotors be bad right out of the box, they are not as easy to put out there as many think. The 5.5 number is too high but some rewinders add a bit more winding to make more charge and it may be OK.
 
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