Long story short Hubster.

Against my better judgement, I loaned out my ZX-6R to a buddy and within about 20 minutes he had overrevved it and blown the AC generator stator coils out, bike died and had to be towed home.

I'm getting about 12-18 VAC at 4000 rpm, book specs calls for 53 VAC at 4000 rpm.

It has to be either shorted stator coils or the permanent magnets in the rotor have lost their field magnetism.

I have ordered and received the new stator and am going to put it in next week sometime and see what I have.

Have you ever seen rotor magnets lose their ooomph or is the stator the weak link here?

* Last updated by: Kruz on 10/8/2024 @ 8:12 PM *

Probably the stator wires. Once removed, you'll see black coil windings, and the rest will be copper in color. Magnets are pretty robust and hardly breakdown... my experience. Pretty much shows output on the test, so my guess are the coil windings.

Charge that battery up while in limbo.

Can't blame the buddy. Just a bad run on the stator. Check for loose magnets. Just pulled a rotor off my nephew's HD shovel and found a loose magnet block. For whatever reason I removed it, it was not the OEM year for it. Took the mighty Amazing Goop Glue and glued it back on. Will last the oil and heat... ask me how I know.

If say the stator looks unburned at those cores, then check the magnets with a metal washer, nail, to see if one block is weak to the pull off.

Ok good information, thanks Hubster, my guess was burned stator windings (shorted) when I saw the low AC output at 4000 rpm. Book calls out the winding resistance between the three phases but the values are so low, almost 0 ohms, that my multimeter just showed 0 ohms. The new stator windings are reading the same 0 ohm values as the original across the three phases, so my guess is my multimeter is not accurate when reading very low ohmic values. When I pop the gen cover, it's going to be an oily mess correct? I ordered a new cover gasket but will try reusing the rubber block where the stator wires pass through the cover. Any recommended gasket sealant, high temp silicone RTV, Pliobond etc.?

Last time I loaned the ZX-6R out it came back overheated with a blown battery and regulator, kid overrevved it. I've ridden the bike since purchased new waaaay back in 2009, so 15 years with no issues but I stay well clear of the redline. I warned this guy to keep rpm at or below 15,000 rpm or it could blow the regulator and he promptly took it it to 16,500. DON'T LOAN OUT YOUR BIKES!!

John

* Last updated by: Kruz on 10/9/2024 @ 12:38 PM *

Ah, the continuous 'don't loan...' syndrome/horror stories. You know they will twist it up because it's not theirs. Anyway, take a single wire to the ohmmeter and see if going to ground at the stator housing, should show 0. Especially do it to all 3 yellow outputs. This shows zero ground of the 3 yellows.

The one loop might show ground of the burnt stator wire. So ground to the engine or frame, stab a wire. See if this moves the meter. Probably need a fresh 9v for the meter.

Yes, oil will pour out on the side stand/using a center stand. More lean the right handlebar on the garage wall. Place in gear. I think the stator is inside the dyno cover so no need to remove rotor. Look for out of round dyno cover placement. Meaning, are the dowel pins showing a straight tube diameter? Maybe tagged the bottom of the dyno cover and moved the pins to an S-bend.

Install gaskets dry. Remove any debris that could cause a hydraulic leak if gasket material is left behind. The good shit is GM's 'Mr. Goodwrench intake manifold sealer' for the wire leads out. Any GM dealer parts dept. It's in a black tube. Kind of around 12 bucks around here. Just used some dabs to set the paper gasket on the HD the other day.

* Last updated by: Hub on 10/9/2024 @ 5:46 PM *

Good stuff Hub, Ill try the Mr Goodwrench product....

Hubster are these special cut bolts necessary to guide the stator cover on straight onto the rotor magnets?
Saw this on another forum, makes a certain amount of sense.

John

* Last updated by: Kruz on 10/10/2024 @ 6:56 PM *

The dyno cover kind of self centers with the dowels. That stud idea is pretty much overkill LOL. On the other hand, that scrub down [if any] would come in handy then. So look for scuff marks, the dowel's straight integrity and all that.

Ok thanks Hub...