Battery Voltage / Regulator/Rectifier & Stator Test 

if the stator fails the ground fault test- there is NO NEED to go any further. I doesn't matter what the AC output is - the stator is dumping voltage to ground- the stator is bad. Now, if the was no ground fault- then sure, do an AC output test; absolutely.

Glad to help! Thanks for Liking & Subscribing!

Great to hear & thanks for the view! Here is an updated video on the topic, I hope you will check out the channel! ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

Thank you kindly!

Thanks for the view! you did not mention what year your VFR was so check here bikersrun.com/search?q=VFR+Stator&options%5Bprefix%5D=last

Lead Acid battery? If so its sulfated and time for a new one.

@@RodRidesWrenches It's a lead one barely 3 months old.

@@RodRidesWrenches... So the rectifier is ok? Or I should worry!

@@dandenyo3847 If the rectifier shuts off the reverse flow of current it is fine. The readings you took are close enough to the same. When testing the rectifier it is more important to have the reverse current flow stopped by the diodes than the readings on your multimeter. This may explain better ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.htmlsi=qIGAIRpSBseMcbcj

@@dandenyo3847 When you asked teh question I assumed you were having issues with your charging system, is the battery going dead while riding or sitting?

Hi Westley the other wires are typically green or brown or stripped variation. These are not the live wires from the RR just the black and red ones. Yes it sounds like the RR is bad. I have another video that may better explain.

ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html Good luck!

It sounds like you have a MAJOR short in your wiring. Something is grounding hard. If there are ANY accessories on the bike (heated grips, charge ports, accessory lights) disconnect them these are the most common suspects. Get a voltmeter and measure voltage drain with the ignition on, and off, you'll know you found the problem when you see the voltage drain slowly after disconnecting the offending part. After that you need to chase your wiring from the engine handlebar kill switch which again is a common problem for shorts and failures ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-W0MTZbtMgOw.htmlsi=DnYLDlUxGccKgXtB&t=560 to the ignition switch, to the kick stand switch, and all the other things like clutch switch and tip sensor if equipped. You did not mention what bike you have so Good Luck on the short fault hunt!

Thanks for the reply, I’ll check it out

I did what you told me and there is a short. The battery was slowly draining when I tested it with my multimeter. I just now need to find it

It only drops to around 10 volts when starting shouldn’t that be enough to start it?

@@user-by5ud2hf1p Yes it should

Hello Charles, did you perform the ground continuity test as demonstrated in this video on the stator? What was the result?

Hello Airi, 16V is too much, maximum Honda Service Manual specifies for a depleted battery would be 15.5V Is your voltmeter accurate? If yes then it is your voltage regulator/rectifier as the issue. Too much voltage will not only burn your battery out, it heats your wiring harness and will lead to premature failure or worse, fire. Good Luck!

Thanks for the sub! You may find this one better explains how the rectifier works overall. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

You set your multimeter to measure continuity and not voltage correct? If so then yes the regulator is dead.

Thanks Larry I have another that goes into a detailed explanation on how your RR works here; ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

No there should be continuity between phases in the stator. If the phase poles are grounded, this means there is a problem. Here is another test that just focuses on the stator ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.htmlsi=Dg_Q6YkeYAuZg1Hd

Lots of things can be the problem... What is the battery voltage after you try and start it? The voltage coming off the charger is artificial due to surface charge on it. The most common issue is the battery is bad. The starter relay can be bypassed to check it or just get a replacement and try it, they are not expensive. The other common issue is the right handlebar kill switch. These switches get gummed up with dirt and the circuit is not strong enough to start the bike. Finally there are your battery cables. Cables corrode over time and if they are green with corrosion, frayed or loose on the other end (not the battery I assume you tighten that properly), you need to address or replace the cables. Here are two videos that you may like, one with a hard to start Ninja 600 ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-W0MTZbtMgOw.htmlsi=hSXqS227xUin5aNt The other discusses issues around the charging system and shows additional ways to test your charging system. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.htmlsi=ZIvJuzMQBserzW2w Good Luck!

Thanks for the Info @RodRidesWrenches, will definitely try out and do the other checks ✔️ hopefully I manage to trace the problem..

Your battery is sulfated. Fully charged your battery should be 13-13.3 VDC. Each cell should be 2.2VDC you have 6 cells in a 12 volt battery. you can try using a battery charger that pulses like this one bikersrun.com/products/motopower-mp00205a-12v-800ma-automatic-smart-car-motorcycle-battery-charger-maintainer?_pos=1&_sid=83f767274&_ss=r or replace the battery. You should still get that charger since it will maintain your battery and keep it from sulfating. Regular chargers don't do that. The other problem may be a parasitic draw. disconnect the battery from the bike and leave it sit for a few days, hook it back up and see if it works. If it does then you have a draw somewhere. Obvious places to look are any aftermarket accessors; heated grips, lights anything running off the battery. Disconnect them with a voltmeter on the battery and you should see a difference when you found the one that is drawing current. Or just try disconnecting them them one at a time until you find it. - Thanks for the question & good luck!

Voltage at the battery while the bike is running is controlled by the Regulator Rectifier. The RR is metering the state of charge of the battery (low voltage battery higher output from stator to the battery and vise versa) as well as the load the bike is demanding from your electrical system (high beam, heated grips). Li batteries have battery management systems built into them to prevent overcharging because overcharging a Lithium battery results in a "Thermal Event" than you can't stop by spraying water on it. This being said, 15V is too high for a Li in my opinion and you should check with the Li battery manufacturer for their specification for your model of battery. If I were you, I would, fully charge my Li battery with a proper low amp charger and check it again in the bike, if the condition of 15V remains, replace my Regulator Rectifier and or battery to an AGM one, to confirm the issue is with the Li battery and not the bike. BTW if you cannot fully charge the Li battery with a 1-2amp charger, your battery is the issue. Also the charger should be old style analogue with a meter to do this test, just make sure it is set to no higher than a 2 amp charge. - Good Luck!

@@RodRidesWrenches well, i am sorry but that was so not my question, something was misunderstood... not all batteries have BSM, and i was just wondering what is the chance that my bike(or any other bike for that matter -hypothetically) charges with 15+V... in 2 days i will have voltmeter to measure it; up to 15V is ok according to manufacturer of LIFEO2 battery that i installed yesterday... bike is 4 years old and has bluetooth connection and stuff so i imagine it uses an ok regulator but who knows... electricity is not my forte

Thank you and I hope you have subscribed and checked out the channel for more motorcycle stuff! ru-vid.com

Glad it helped

Sounds like a weak stator, here is how to test. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.htmlsi=ipdeUP15o3p41OvJ

You have a failed stator most likely measure ac output off the stator as shown here ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

Great to hear it helped you!

Thank you Otis for the feedback & Views! If you're interested in know more about how these systems work, check out ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html and the rest of the channel is full of more useful stuff. Ride Safe!

Hello Leonardo, if your battery is getting damaged it is most likely the Voltage Regulator & Rectifier. I also have this updated video that shows some additional tests you can do ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html Thanks for the feedback & the views and good luck!

Hi Mac, Sounds like you've just about had enough stator and battery problems. I would not recommend using used parts unless you know they are off a working bike. The OEM stator is no longer available but I have heard of VFR owners upgrading to the 6th Generation Stator & RR but I have not confirmed this myself. My 2000 VFR800 has the same stator connector as my 6th Gen but I didn't change that one as it is still working well, see video ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html You can get good stator and rectifiers from a new company I have been working with for the past year and really good pricing & free shipping. They work with the manufacturer overseas. Here is a link to a new stator rebrand.ly/l243bgb Here is a link to both a brand new stator and RR in one kit rebrand.ly/dwldjbi The other thing I would look at is parasitic draw. Measure your open circuit voltage with the battery installed on your bike and record VDC. Disconnect the ground cable from your bike and check again, did it change more than 1 tenth of a volt? Look for accessories to remove from power, sometimes things like heated grips or aftermarket lights can break down and draw power even when turned off. You said you replaced the battery with a new one. Running your battery completely flat is detrimental to it for sure but what you described does not sound right. The 5th Gen VFR puts out very low current at idle or low RPM, avoid getting stuck in traffic leaving your engine run, learned that the hard way... Make sure when you buy a battery you get one with a separate acid fill pack that you have to load into the battery. This way you know you're not getting a half sulfated battery that has been sitting on a shelf for a year. Better yet get a lithium ion one, pricy but worth it is you bike sits for extended periods. Good Luck and let me know how it goes!

15V is too high. Check the ground strap to your battery & replace, remove the RR and clean the mount to the frame. There needs to be a solid connection between the RR and the frame so it can shunt voltage back to the engine. SEE VIDEO ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

You got what?

When i was checking it like you did, one male end read 1260 and the other 550..@@RodRidesWrenches

Hello Edwin, The condition you described is most likely faulty ignition coils. The RR would not prevent your bike from starting. When bad coils heat up they are unable to generate high voltage. Check the ignition (spark) at the spark plugs when the bike is hot, trace the lead and change the coil(s) out with a new one to find the culprit. This being said, I would just change all the coils and wire leads since any that are good now will probably fail soon. - Good Luck!

Hello Francisco, based on what you have done I would say you have a faulty new regulator rectifier. Test the RR transistor gates as shown in the video, I believe if you swap the RR part with a known good one, this will fix your problem. Sometimes you get a bad part, even if its new. Secondly confirm all ground cables are good, replacing them is also inexpensive and will confirm you do not have a ground resistance issue. - Good Luck!

Glad to be of help! Hope you subscribed I have a masterpiece video coming Saturday the 29th!

Thanks for the feedback & View!

Awesome, Thanks for Liking & Subscribing!

How do the coils in the stator look? Are they burnt? Is there continuity from the leads to the pole frame? No need to put it back in the bike to test that, the second video in this series may help ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html How is the ground strap from the engine to the battery, any green or black oxidation? A bad ground will weaken the spark. - Good Luck!

@@RodRidesWrenches the coil condition doesn't look bad to me but that could mean nothing...the bike is a new build so condition of wires and contacts are all very clean...the problem is I'm fouling plugs as if weak spark..carbs are new and jetting should be good...I'm going put in line spark checker and continue troubleshooting...I do have an nos stator coming...thanks for reply

Hello Legin the coils are insulated from the poles when working properly. When the coils breakdown they ground to the poles which are in contact with the rest of the bike. The stator leads do not ground when working properly. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

Great to hear it helped you!

Thanks for the view, you'll find many such videos on the channel and more in the pipeline. The only manual worth owning IMO is the factory manual, yes they are more $ but are worth it. 👍

@@RodRidesWrenches Yep will look into it

If the continuity test did not go to ground then it could just be your battery. What is the open circuit reading on it? Bike turned off, fully charged, how many volts? It should be around 13V (2.2 X 6). The stator can fail in sections basically as one phase (section of coils) burns out, then the second. By the time two sections have burned the stator fails. At 14+ volts it does not sound like the stator. Does your voltage drop while the bike is running at idle, working its way down to 10-11 volts? ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-bUb97GnDLOU.html

12.5V is just fine for idle! As long as you do not go below 12V, if so then replace the battery. The fact that your voltage goes up to 14V means your stator and regulator look good.

Thanks for the view & feedback, you may also like ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

WARM yes HOT no, bad connectors, corroded wires (battery cables especially, see any green corrosion?) faulty grounds, failing diodes... More here ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

Yes check the grounds, the cable from the battery to the engine can get full of corrosion. The more I think about it, the more I go back to the magnetic rotor. I have head but not seen these needing to be replaced. In some years Honda had a bad batch!

What is the voltage you are getting at idle, what is the battery voltage at 5000RPM and what is the voltage you get at 5000RPM with the high beam on? How old is the battery you are using in your bike? Check the AC output on the stator with the bike running as I described in this video ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html The stator may not be grounding but the coil packs weak. Also described in this video is a transistor continuity test for the RR. Confirm your ground cables from the battery to the engine are not corroded and that all your connector pins are aligned properly and making contact with each other properly.

@@RodRidesWrenches Thanks so much for the reply! I watched the additional video and it was very informative. The battery is only 2 years old. The bike’s voltage is around 12.3v with the high beam on at 5000 rpm. No change from idle aside from it decreasing slowly. I tested the stator AC output while the bike was running and got zero across all 3 phases. The rectifier passed the tests however there is a parasitic draw that only goes away when I unplug the rectifier connection to the rest of the bike ( not in between the stator and the rectifier). I am leading towards replacing both the stator and the reg/rect but do you think there may be additional problems? I checked the ground at the battery and on the block, both have been cleaned up but still no change. Any other things I should check or do? Thank you so much for the help in advance!!

​@@xIIxpetey454xIIxUnplug the stator from your regulator rectifier, does the parasitic draw remain? If yes then there is a diode issue in the regulator. If not then you now know it is the stator that has a ground fault in it. For whatever reason your multimeter did not pick this up on the continuity test. Make sure when doing the continuity test you have a clean ground to the engine case. A faulty stator can drain down a battery with the ignition off. - Good Luck!

Here is the Stator Replacement. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-821GZTRqM2o.html Good Luck!

The Stator is the same on the 5th gen so yes those three wires. Remember there is no polarity on the stator because it is producing alternating current on the three wires or three phases. It does not matter which wire goes where on the stator side, that's why they are all yellow in color.

Thanks for liking and subscribing!

Thanks for the kind feedback. I made an update to this one recently that goes into more details on the RR and Stator please let me know what you think ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

Thanks Scuba Steve!

The brown wire on the harness is not required. It is for an accessory. Ignore and carry on...

Check/Replace your battery cables, both of them. You didn't mention how old your bike was, most bike should have their cables replaced if you have intermittent electrical, specially in a 20+ year old machine. How warm are the cables after a short ride? Likely a loose connection is causing your grief or excessive resistance, caused by internal corrosion, see any green corrosion on your copper wires? Good Luck! ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

Thanks for the feedback & View! You can find more information about how these systems work here ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

Please clarify what you mean by Feul Niddel? Fuel Needle in the carb?

Your bike uses an ignition system where an electric charge is stored in a capacitor then discharged through firing the spark plug. CDI ignition boxes are the weakest link in these ignitions. Check your two wires out of your stator by measuring AC voltage. If you have voltage your stator is not the issue. Get a manual for your bike, it will tell you how and what you can check next My money is on your ignition capacitor but this is based on the fact it is a dirt bike and these are a common failure. Obviously you've checked all the leads to your coil and being a 2017 it should have an prom chip that clips into the harness under the seat or by the forks (I don't know about Yamaha's placement, check the owners manual) if this chip is damaged or not installed properly you have no ignition. Good Luck!

Thanks Avinash there is an updated video that explains how these systems work you can find here ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

You're regulator rectifier is most likely gone if you're getting low RPM voltage but did you turn the headlight on high beam? The additional load is required to get the accuracy, especially at idle. Ground test the stator as described, if the poles are weak this could also be a factor ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

The cause is wear, nothing lasts forever, especially high voltage generators. If you have issues with repeated problems check out this follow up video I put out today, it runs through why your stator may be continually failing,. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

Sorry to hear that, have you changed the regulator?

@@RodRidesWrenches new battery, genuine Honda rectifier and now I have a genuine Honda stator. I have seen a post about the fly wheel may need upgrading and sometimes that does the trick. At the moment I have a touring bike which doesn't tour. I will be checking out the issues and hopefully I can sort it out before I'm 200 miles away from home the next time. Thank you for the video. I will learn to spot these issues.

@@anthonyburrage6603 The magnetic rotor is all that is left to change by the sound of it. I have heard but never seen these needing to be replaced. Let me know how it goes!

No here is how ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-821GZTRqM2o.html

Hi Lambo I would think it is the stator connection to the Regulator if I were speculating. Bent or broken blades. If the Wiring is good then could be a fault in the new components, sometimes new things are just bad but that is what warranty is for. Finally the only other item that comes to mind is the magnetic rotor. If, for whatever reason, it is unable to create a strong enough field around the new stator poles... I have a new video out Sunday that may further assist. Good Luck!

@@RodRidesWrenches thanks for reply. I did more tests and foaund out that the brand new stator I got was a faulty one. Finally found my problem. I'm only learning about electrical stuff I'm more mechanical guy so took a while to find problem. Thanks Alot for help 👍👍

Regulator Rectifier is on its way out. Change it before it leaves you stranded. It's happened to me a few times and it's no fun. 😶

@@RodRidesWrenches Thanks! I'll get a new unit on the way. Yeah, being stranded on a bike sucks. Now I just need to get a bike lift, got three other bikes to work on.

What did you test? Continuity? AC voltage? Resistance? This may help ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

@@RodRidesWrenches I tested the voltage AC. I got reading like .78 .28 and .64

No not the RR I would point a finger at the battery first. how old is it? If it is an AGM or wet cell your voltage should be over 14V at 5000RPM. If it is lithium like the one in the video then you are okay at sub 14V. What is the voltage on the battery without any load (bike off fully charged). If the voltage here is under 12.6 definitely needs replacement. If the battery checks out good then the fault would be back at the stator. Do a phase to ground test as shown in the video.

@@RodRidesWrenches battery is just a few weeks old, but it let me down once already, hence why I was thinking reg/rec. 12.2 volts without any load. It's a nitro battery, not lithium, probably AGM or wet cell. I've already got a regulator ordered so I'll fit it and see what happens, will probably replace the battery with a more well known brand too. Thanks for the reply 👍

@@seanoghughes95 A new fully charged battery should be 13.2VDC 2.2 Volts per cell X 6 Cells. Because of variance in meters and shelf age of the battery I was looking for 12.5-13VDC. Install the RR but you may have a battery that has sit on a shelf for awhile. If the battery is prefilled and sealed like an AGM or GEL then the chemical processes inside are already happening, regardless if it is hooked up to a bike. Here is how and why ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-xXkq-p59oao.html

A healthy Stator will not have any conductivity to the rest of the bike, it doesn't ground out from the leads. If you want to measure the AC Voltage from the stator check out this video ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html

2004

Thanks for taking the time to view & comment!

If you have 14.5 v at 5000rpm your regulator is fine. If your voltage drops off at idle this is normal, the average lead acid motorcycle battery can't maintain voltage for extended period at idle. If your volts drop quickly at idle your battery could be weak needing replacement or your lights/bike is drawing heavy amperage. Most likely the former but if your bike's wiring harness could have corossion leading to more resistance. If you have a voltage issue start with a high quality battery. Lead acid batteries wear out and sulfate easily get a lithium best money i ever spent on a battery. See my battery video for more.

ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-xXkq-p59oao.html

@@RodRidesWrenches thanks a lot for your reply. If I would like to change my regulator for a Mofset, is it better than the stock one?

@@giovannimaraniello4073 mofset regulators build current and are basically one circuit, they run cooler and do not load the stator as much to create the equivalent voltage because of the current build up ability, my understanding. The normal diode regulator works fine. If your current regulator is burnt try the mofset, from my real job i know there is a shortage in control chipsets for them globally. If you can get one at a comparable price then give it a shot, it is better. I am personally okay with the diode type for the type of use I have on my bikes. Good Luck!

Thanks for the feedback & view!

Thanks for the feedback & view! There is an updated video here that goes into more detail on the inner workings of the regulator rectifier ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KpmvUvpRCEM.html