How To Test A Motorcycle Stator 

Stator to ground tests should be done with the engine at running temperature because the wires could have a short that is so small that it won't actually short to ground until it's swollen with heat. In such a case, cou might get a good charge at first, but the alternator would stop charging after a few minutes on the road.

TheMotorcycleMD I have watched a lot of videos here on youtube on checking the stator. I will tell you in my opinion, yours is the BEST one. As far as making it seem really easy and not adding any extra hooplah, you kept it simple and on point. Thank you for making and sharing this video. I really do appreciate your time and effort.

It always makes sense when you have explained it. I think your a natural teacher. Thanks a lot.

Best Teacher Yet. Calm walks you thru step by step. keep it up Sir

Thanks for video! I'm checking this tomorrow on my Suzuki!

Your videos are world class. Thank you!

Did all the checks with the stator test & regulator test.All the tests checks out.Checking this due to the '86 shadow vt1100 I just picked up had the issue in one of your previous issues with the burnt connector coming from the stator to the regulator.

Dude, I have watched 3 of your videos, and have learned a shit-ton. I’m reconditioning a minty fresh looking ‘00 VFR, and of course the reg/rec is shot, but thanks to you I KNOW that is the problem, rather than just guessing.

Man bro SAVED me some 💰. Thanks again your vids are superb and, very informative to riders. Subscribed!!!

Thumbs up for clarity. Thanks dude!

Brother you just helped me out a ton , i appreciate you putting out this video 👍

Excellent video! Will check it in the morning. Thank you

Dude you’re awesome. Clearly explained. I’ll be checking my vfr1200f today due to having battery issues.

WARNING: stator winding can give 0.3-4ohms & still have faulty Voltage output, so need to also test for AC @4,000rpm =@50Vac. ..in all 3 terminals. Essential to test stator ground, ohms & also Voltage output. 😎

Thanks for your time

ok, you got the readings that you wanted to show the stator is good. What would be the readings for a bad stator. Thats the real question. You missed a very important component to this type of testing

Ok to clarify. In a factory service manual it states a resistance range for yellow to yellow measurements. It states if you have no resistance (ol) or anything higher then they state then your stator is bad. Also an AC voltage check should be done and the measurement is taken with your meter on two yellow wires and at a specified RPM. at the rpm mentioned in the FSM it states the AC voltage reading you should see.

Thanks for showing

This helped so much thank you!

Awesome video man, cheers from Aus 😎

thanks for your video sir it help me slove my friend bike :)

Great Video ... TY

Best explanation on this bike in general. You have a video on a stator removal/replacement?

Finally found a good video, that explains how to text the stator!!

Thx for the videos. God bless ya ✌

@themotorcycleMD, OL in multimeter means "open line" which means infinite resistance or the line under test is broken or no connectivity/continuity

Great video.

Thanks brother

great video

Excellent 👍👌

U r amazing thank u for all ur help but I’m not that great wth my everstart multimeter When u say ohm can u specify which ohm # becus 20m 2m 200k 20k and down to check the stator harness’

Thanks, do you have to do this at a specific temperature? Reason is my bike is out in the cold.

Thanks a lot man ! I will do this on my VFR800 as i suspect the stator is going bad

I have a '87 Honda Shadow vt1100 that i shook back from ten years of neglect that was doing great for about 15 to 20 miles then i lost fire... I chased down a couple problems so far... might cdi had a transistor burnt to my coils. Replaced em. Problem unresolved. Pulled the whole electrical system. Checked coils. Both were good. Pulled the regulator and the wiring harness on the 3 yellow wires seem to have grounded out and melted the plastic... is that gonna be a bad stator? Haven't come across any other faulty connectors or any electrical problems other than no fire to the plugs on my front cylinder.

ok so this tells me that my stator is bad tanks! but the previous owner scolded the wires to the from the stator to the harness (removing the plugs) so dose it matter wich of the 3 wires from the stator go to wich of the 3 harness wires?

also can i use a universal 3 terminal rectifire for my bike

Hi, when testing my stator coil resistance on my cb500 98 twin i got 3 readings of between 0.3-0.5 ohms. According to haynes manual it should be 0.18-0.20 ohms resistance. Would my readings suggest a fault with my stator or is this normal? Thanks in advance

now i noticed your resistance readings were upwards towards .7+ is a lower reading such as .2 mean anything negative?

Thanks for useful video. If two of the three( yellow ) wires got crossed when removing a suspect plug joiner, (that links to rectifier / reg') would this cause problems? I'm on my 3rd regulator in as many months. ( Honda cb 600 2002) The third regulator is now an original part. ) Going off to do those tests now. Thank you

Changing stator on 94 vt1100c and almost done scraping the old green crankcase gasket off. With the new paper gasket do I just make sure the two surfaces are clean and dry or do I need to put a sealant on the paper gasket first. The criss cross with a torque wrench afterwards I think I have down.

My stator is grounded :,(, but I get to buy new tools to take bike apart. So I guess I break even :) Edit: Thanks for the vid. Great explanation

Thanks easy

How do I determine the alternate output on a stock 2007 Honda VT750DC Shadow Spirit? I need to know if there is enough surplus power available for driving lights, heated grips, etc. I can't find the info in the service manual or owner's manual. Thanks!

My stator has 5 wires. 3 of them are black. One is red and the remaining one is black with white line. I presume the 3 plain black one are the same as the yellow wires from the stator coils while the red is a positive and black/white is a ground wire. Both the stator and the rectifier do not have connecting harnesses. The 5 wires from the the stator are connected to the rectifier’s 5 wires with electrical tapes! I suppose the last owner cheaped out on the harnesses. My questions is: do I probe test the 3 black wires only to carry out the resistance test and the continuity to ground test? Or do I have to check the red wire and the black/ground wire as well?

You don't have to test all three stator AC poles (wires) for connection with ground. One is quite enough because the three wires are all internally star connected. If there's connection with ground, they all are grounded.

Hey man i was wondering if you could explain in detail what each of the tests mean. explain the troubleshooting system in detail from sign to source?

Hi, great video, on a Ducati 750ss I get resistance of 0.01on all 3 yellow wires going down to the stator, do you think that's ok, the rectifier seems ok, I've diode tested it like in your other video..us I've put on a new Exide battery, the symptoms are that as soon as I put dipped or main beam lights on I get a red warning lamp on, so any load and I get a warning lamp, at idle when there is no load I get a very dimly lit red light, if I rev up it goes away sometimes...put lights on and it's a full on red light, the battery is getting 13.7 volts with the engine running ...so I dont really get why I'm getting a battery warning light....any ideas on what it could be... Thanks Ian

I have seen stators overheated so turns in coils touching each other, electrically now u have less turns, so u get less voltage built up, but no short to ground. so if u have a number of coils that have shorted turns, u get less voltage from them. if the stator is rated for 25 amps and its voltage is less due to shorted turns u lose power as watts are = to volts X amps.

Tq

Nice video. My problem is this: the rectifier gets too hot and it fries. I replaced but the new one have the same issue. I've checked the ac from stator and I get 52v from all 3 yellow wires. Is it normal? This is a scooter SYM VS125. Any suggestions?

Unless you have an expensive, highly accurate multimeter (it is not called a volt meter as you said), the meter may not be sensitive enough to give you accurate readings for certain stators (depending on the manufacturer) on a static test which is what you did in your video. Most people don`t have an $800.00 Fluke multimeter laying around or something even similar to it. There are specific ohm tolerances for all stators and all 3 windings have to be within that range that the manufacturer calls for . You are much better off doing a dynamic (engine running) test between the stator leads (you should get 20 to 30 volts A/C) - that shows if the stator is actually sending out voltage! There are much better instructional videos out there, Revzilla is one of them, do yourself a favor and watch one!

Hello, I have a 2003 Suzuki Savage with a weak charging system. Did these stator tests and yellow to yellow had resistance. When I tested yellow to ground I would get fluctuating resistance numbers on all three but eventually they would all go back to .0. I changed the regulator per my mechanics recommendation but that isn't helping improve the charging system. On the regulator black to battery cable I'm getting 0 with the key off and only 0.12v with the key turned. Is that a problem too? What are your next step recommendations? The Savage charging system only has red and black cables exiting the regulator. Thank you!

Thank you, very good video, now even a dummy blike me can do it..

I am getting a resistance reding of 5.7 ohm in all 3 connectors in my cbr 250r. is it normal ?? or the stator is damaged.

What about moving the harness to ck for a run though and what about the put out of the stator can be week and still show no opens or grounds

Hi buddy. Great videos. I replaced my stator, done these checks an fine. But I'm not getting any charge out of the stator. Do you have any advise I could use please

Is it possible to have a 0 read for continuity and a 0 read for resistance?

Will there be any problem if the inside of the stator magnet rotor is scratched ??

+TheMotorcycleMD I know everything has a "flow" meaning it starts from A and goes to G, or whatever the case. If I turn the key and the lights come on, A, the battery is good. But if the petcock is open, the kill switch is on run and I hit Start and I get nothing, meaning I hit start and the power dissolves, does that mean that stator is bad?

You sound like Dante Basco with allergies. Haha but seriously tho good video.

Help! My bike is not firing on the left cylinder. I have been replacing parts, trying to understand the manual, and even wired a new harness, but it still won't fire.

I was hoping you would do an AC test on the Stator. I have an Issue with my charging system on a 92 Virago XV 1100 ,I have change three different Voltage regulator, on one of them It is putting out 17.5 V ,I know that one is bad ,tried another one and it will not go over 12.7 volts so is the third one , I have bought two new one on line it will probably come in some time next week.

how to cheque the stator on a xlr baja md22. mine havent got a battery from factory

I have a 99 V45 Magna I may have a stator problem Would I be safe in getting a NEW stator off E Bay? If so who would you recommend that I get it from? If not could you recommend a good shop to purchase the part from? Thank you.

On the stator connector there are 5 wires. You've discussed the three yellow wires. Is there something you can add about testing the black and white wires? The manual suggests a reading of 10 - 12 Ω. If there is no reading when checked, what does that tell about the state of the stator (other than being SOL) ? Thanks.

I've got an 84 VF700 it's my first bike I'm trying to learn about what's wrong with it. I've just learned what a stator was I think mine is going bad. My bike will start up but it idles like crap sounds like it's missing you can kinda feel it when I'm driving under 30 mph. When I'm sitting there idling you can kind of see my headlights and running lights flickering with the idle speed. Sometimes it wants to die when I come to a stop. I gave it a little tune-up when I got the bike about 4 months ago and the plugs fouled within those four months I put new plugs in it and it's still running as mentioned above.

Hi MotorcycleMD. Shouldn't the ohms for all 3 wires be the same? If the ohms are different, doesn't it indicate that the stator needs to be changed?

Would taking a voltage reading from the stator also prove that the stator is good?

I check my kz1000,I have zero ohms on all 3 yellow wires,is stator bad?

Can it be done the same on a drz 400sm

81 cb750f f super sport Checked rec/reg, stator , rotor , all good , then saw that the outside brush was worn down and not making contact with the rotor . CHECK THIS TOO,

I got 0.8 of resistance when I checked the stator wires, I switched positions and all 3 positions I got about 0.8 and when I checked from the battery to the alternator I got OL .. my battery keeps draining after a couple of days (to the point where I can ride the bike and then shut it off then try it start it again and it’ll crank but not kick over due to lack of power) and I don’t have anything hooked up to my battery. It’s a new battery I bought last year, I did replace my voltage regulator last year but may I need to replace the stator.. ??

Im reading 77v AC on the hot wire (black/red stripe) going to CDI from stator at idle. When i give it gas it only goes up to round 87 v AC. Don't know if this is sufficient. Im having problems with the bike Honda GLH 125 riding fine at low revs but as soon as i start stitching it a little the revs cut out & it like splutters & almost dies or misses until i let off the gas & the revs decrease to a low level then it runs fine again. Carb is clean, new plug & ignition coil. Im suspecting its the CDI as the problem started initially with one of the wires near the CDI shearing off disabling the bike completely until i reattached this wire but then discovered this problem I've just described. I have tested the stator for ground issue but don't have a decent fluke or such. Im about to check the voltages on the 2 phase stator( i assume as it only has 2 yellow wires from the stator) while the bike is running & at revs of around 4000. I have no battery or starter motor clearly, i only kick to start. Haven't used the electric start since I removed the battery. Ok i think i just found out its not an issue with my stator as it probably wouldn't even start if the stator was fried. Could still be an issue with the wires running from my stator and its single phase as there are only 3 or single

"ground" that a different expression for "neutral" (on battery) on you touching the bike frame?

Does this test apply to 2008 Honda Shadow VT125?

I’m getting 0.2 ohms of the resistance reading.. on all 3 phases. Is that still good ?

Thank You for sharing your experience with this...I went to test my stator and found the plug melted LOL 😂 i went ahead and done this test hoping for some luck...passed the ground but not the broken wire... I'll be replacing the regulator and stator do you know of anything else I need to check while I'm into the teardown? 1998 VT1100C3 AERO Thank's again for your help and sharing Brother...✌️😎👉💥 Smashed Your Subscribe Button too

hey do you have to have the battery in the bike when you test it to ground?

So not getting a reading while checking the resistance between the wires is bad?I only get from only one wire to another other 2 have no readings between them

do you test with the ignition on or off? I checked both ways and get high readings from all 3 wires 1,*** & .9** : According to this test, my Stator on a CB4oo sf is faulty?

Ok, i have a Honda Shadow 750 1983. I did the check as instructed. Two of the three wires show resistance between the leads and the ground, third shows OL. On the second test, one of the leads shows OL when i test it to other two wires and the other two show 14.7 ohm between them. So, if i am getting this correctly, my stator is fried?

I just replaced my stator cover and it had a little bit of oil in it, is that normal

O.L. actual stands for Open Loop. Also all three legs of the stator should have IDENTICAL ohm readings. If not, your stator may be in the early stages of failure. You should also use a Fluke brand meter. Anything else can give false readings. Especially if the meter cost less than $100. What AC voltage readings did you get?

I replaced my stator connectors. They were burnt. I replaced the connectors with butt connectors. Now, the charging system is working. I noticed the stator wires from the stator too the connection too the rectifier get quite hot at higher rpms. Is this normal? Makes me think the the wires should be thicker gauge or I'm still having problems at the connectors. Their is no heat at the rectifier end of the connectors. I used butt connectors. After, seeing some of your videos, I'm thinking of hard wiring with soldering. Though, if the wire is the culprit (being to small a gauge) the stator wires will still get hot at higher rpms. A better connection may solve it. Also, the rectifier wires are the same gauge as the stator wires. So, is it normal for stator wires to get hotter at higher revs? and if the stator wires should be larger gauge?(note: Stator wires are the same gauge as the rectifier wires)

I have seen ton of videos about checking the stator, how come nobody does "phase to ground voltage measurement" when running?

How do I check the regulator

Is this with the bike with just the key turned ?

i check mine two of them give sign but one of them give. ... I ... open line on my multi meter does that mean it's spoil already any ideas ?

I boutgh an 2001 OEM stator for my 98, and the both have 3 yellow wires but the 2001 that came with the same harness the shows in the video. Mine had 3 straight yellow wires from the stator to the rectifiers. Now, does it matter which yellow wire goes into which port? If that makes sense to you. People on Shadow Forum told me that it doesn't matter which yellow you put in ot what port.

How do I do this on a cafe racer 1983 as battery not charging and where’s get meter from please

I dont seem to be getting a resistance reading when touchibg wire to wire. Not completely sure im touching the correct wires, think so but its made in a dofferent way. I AM however getting a resistance reading right before touching the metal ending of the wire when i touch the silicone water protection thingie on my way reaching for the metal part. Would this indicate my Ststor is fucked or? Someone help? Electricity really isnt my spectrum so dunno ehat to do with this info.

thanks for the vid I checking the AC output from my stator when the engine is idle and i am getting only 10V AC, is it means my stator is bad? ( the resistance check and ground check all seems ok)

After changing my battery and regulator/rectifier 4 times can anyone give me advice on this. I've done all the checks in this video and compared to the manual plus removed the alternator for a visual inspection but after around 6 months both the battery and reg/rectifier need replaced with the 30A fuse blown. Any ideas? The battery will also drain over 4 weeks needing replaced if the bike isn't used but I can't find any decent parasitic draw, just what the ecm is using which is minimal.

OL means open line. Open circuit meaning no continuity.

Is it possible for the stator to show 0.00 ohms and still charge? I ran this test and it failed, but it is charging the DRZ. I ask because me DRZ sputters and misfires once at operating temperature like if it were hitting the rev limiter. Have not used your method for the coil…that’s the next test. The rev/rec tested fine…which is what the Suzuki dealership said was most likely the culprit

What if I get 0.00 ?Please help Thanks

Hi, here's what i did. Set the ohm to 200 and it was showing 1 and its an ebay multimeter. Step 1: I checked my 3 yellow wire, and the reading is 1.0ohn to 0.9ohm Step 2: I checked the same 3 yellow wires and the reading i got is around 1.1ohm to 1.2ohm Kawasaki Boss 175 - 1999 Do i have a bad stator?

i wanna do a check on a china stator starts but then atv shut out i try startung agian and make a winey noise but no start

So why didn't you do a running engine AC voltage check?

V4 carb vids pls