75 to 77 or 78 Stator Swap??? Help please

650hcs

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I have a 75 xs650 stock charging system, except for a solid state rec/reg from mikesxs. My stator is bad according to curlys guide. I have a 77 and a 78 xs650 I just picked up in decent condition, Can I swap out the stator from one of these? also do I need nylon screws because of the solid state rec/reg? if so, where do you get those? Any help will be greatly appreciated as always. thanks,
 
Stators don't go bad very often, so first, I would double-check your old one. Resistance should be about 0.46 ohms between each pair of the three white wires. Make sure yellow wire is disconnected. Compare readings to your "good stators."

If old one is bad, either the 78 or 77 is a direct swap. See if the old stator has any nylon brush holder screws. If it does, swap the nylon screws along with the stator. Otherwise, you don't need to worry about nylon screws.
 
To add a few points, all the stators from 70 up to 79 work the same. the first few tears may not be a straight up bolt on, I don't know for sure But I do know that from 74 up to 79 they all swap out.
If you didn't need the nylon screw when you put the reg/rec on your 75 you won't need them on the 77 and 78 stators.
Even the 80 stators bolt right on and can be used with your reg/rec. you just need to ground the brown wire brush.
On the ohms for the stators the earlier bikes speced .9 ohms. You checked them white wire to white wire.
The later bikes speced .46 ohms. I think this .46 ohms spec was from the white wires to the yellow wire.
On the stator windings they are three seperate windings that come to a common connection point. This common connection point is where the yellow wire hooks. In the white wire to white wire test you are checking two of the windings at a time, so the .9 spec. The .46 being about half the .9 spec must be checking just one winding at a time.
On testing the ohms I think as long as all three white wires test the same is more important then the actual ohms.
Unhooking the yellow wire is a good idea. This removes the safety relay from the testing. When you test from the white wires to ground and get about 20 ohms, you are testing the windings in the safety relay as well as the stator. Unhooking the yellow wire prevents this 20 ohm reading. It should be infinity.
Leo
 
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Hey guys, I'm new here. Don't post often, just try to read what has already been said about issues I am having. But this is my most recent conundrum. My 81 motor has been giving me all sorts of trouble, and I somehow came up on a 78 motor for just $100. It is just missing a stator. Can I swap my 81 stator directly to the 78?
 
Hey guys, I'm new here. Don't post often, just try to read what has already been said about issues I am having. But this is my most recent conundrum. My 81 motor has been giving me all sorts of trouble, and I somehow came up on a 78 motor for just $100. It is just missing a stator. Can I swap my 81 stator directly to the 78?

Yes, you can swap out, no problem.
 
If you're going to stick with the stock electronic ignition, you'll need to swap the '81 rotor on too. It has a pick-up for the electronic ignition that the older rotor won't have.
 
ok, so this might be a dumb question, but i think its worth asking fore the sake of my motor, since im just a kid in his garage trying to make his motor go... I dont know for sure what carbs I have, I thingk they are Mikuni bs34... if that is what i have will they work on they were working on a 1981 xs motor, will they work on a 78-79 as well?
 
Yes, you need to use the black carb holders from the 81 also. stock air filters won't line up IIRC the BS34 are shorter front to back. Quick tell on carbs; BS34 had chrome lids BS38 have aluminum lids.
 
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