Charging problem

bigborer

Site Supporter
Joined
Feb 16, 2017
Messages
447
Reaction score
78
Points
28
Location
EU
Visit site
2 days ago I try to start the bike- no dice, only the relays clicking. Ok, before this I did some very short trips, and it's been sitting for this long... so it's reasonable to have a dead battery. I fully recharged it.

Friday-the first day of "reduced lockdown". In the morning I learn that I am due for a huge repair bill on my house, after being for 2 months in lockdown and in negative income. To clear my mind I take a ride uptown, intending to pick my GF up and do some 1 hour detour before that.

All things well until at some point I get the check engine light flasing. Few traffic lights later my bikes stalls. Diag mode showed error 46, and 9,8V battery voltage. Around 20 phone calls and 3 hours later waiting and enjoying a fine industrial uptown smell of sewage and french fries (was sitting between a street repair site and a shabby restaurant), I manage to get a bike shop to lend me a battery and my father to bring the battery to me.

I get home thinking please be that I was an idiot and didn't fully plug in the rectifier. No such luck.

The rectifier was fully plugged and yet I got almost zero charge (12,2-12,6V at 2000 to 4000 RPM). Checking the three stator phase wires I get 1-2 0,4 OHM and 1-3 and 2-3 entirely open. So I have a fried stator.

I will try to source a used one, and to be on the safe side also replace the rectifier.

My question is: what the hell could have caused this issue? Did the rectifier go bad and also fried the stator?
 

Gary in NJ

Junior Member
Site Supporter
Joined
May 6, 2014
Messages
1,964
Reaction score
1,908
Points
113
Location
Amoungst the Twisty Roads
Visit site
Stators go bad, just like an alternator on your car. They are wear items. I’ve seen some suggest that the use of LED lighting can cause premature failure of the stator because there isn’t enough current draw on the electrical system. Therefore the the regulator shunts the excess current and the stator overheats.
 

Motogiro

Vrrroooooom!
Staff member
Moderator
Elite Member
Site Supporter
Joined
May 8, 2008
Messages
14,968
Reaction score
1,138
Points
113
Location
San Diego, Ca.
Visit site
I will try to source a used one, and to be on the safe side also replace the rectifier.

My question is: what the hell could have caused this issue? Did the rectifier go bad and also fried the stator?

Regulator/Rectifiers are shunt type regulation. The stator is always under load whether producing current for the bike resources or dumping current into the heat sink on the regulater, Although stator type motorcycle charging systems are often termed alternators, they are not like a car alternator. Car alternators regulate by turning on/off the field windings which create the magnetic field for current generation. The alternator does not have a permanent magnet and must have current from a battery for an active, strong field. The reason motorcycle charging is often termed an alternator is because the stator windings produce current in positive and negative pulses that must be rectified to use with a DC system.

The bike stator generates current from a permanent magnetic source, (generally on a drum) you could call it a generator much like the technology that pre alternator cars used to use, but that old car generator was already producing the DC current (it had permanent magnets) and the regulation was a sophisticated contactor assembly that in some cases regulated current and voltage.
There are series regulators that reduce current and heat produced from constant shunt regulators. Maybe series regulators were not as reliable back in the day but do some desert riding and think about the heat generated in that stator and regulator/rectifier from shunting the current at 100 percent duty cycle.

So heat will be a factor with breakdown of insulation on the stator. I've replaced my stator with a Rick's Electric. they seem to have a good reputation. There will also be mechanical forces at play when the magnetic drum spins in the field already generated within the stator windings. This means that the insulation on the stator winding is dealing with heat and mechanical forces that when failed cause a 2 fold breakdown.

There are few sources of series or MOSFET shunt regulators and there are some knockoffs that are out there that you want to be wary of.

Series regulators are also a way to go that will relieve the heat and constant shunt load on the stator giving it reduced heat and a happy life.
Here's a source: https://www.roadstercycle.com/ OEM Shindengen FHA020AA and SH847 regulators.
Also:
Also look up Compu-Fire series regulators.

Keep in mind there are many fake non MOSFET type regulators out there that will have the part number of a MOSFET but are not that technology. They will work as a replacement but when the time comes for the performance and reliability of the MOSFET, they fail.

I've seen brand names get a bad name when it was fake replacement and not actually the actual manufacturer.

I will no doubt switch to a series system when possible.
 
Last edited:

bigborer

Site Supporter
Joined
Feb 16, 2017
Messages
447
Reaction score
78
Points
28
Location
EU
Visit site
Thanks for the replies!

To my understanding -and I only have very basic knowledge in electronics- as long as there aren't any other issues that causing overheating or short circuits a stator should last for life, as it's only copper wires. I have restored car alternators that had the brushes worn down almost completely, and the stator still was in perfect condition.

I proceeded to take out the stator and beagan with taking off the stator plug. To my surprise the plug was extremely hard to unplug and looked as you can see in the attachment- literally I was this close to my d!ck catching fire and then the entire bike burning off.

What happened was that the spade connectors corroded and this added a huge resistance, and most of the power went into heating the resistance aka the plug form the picture, instead of going to the battery. I mentioned that before that I did a lot of mainenance work- that also included making the low beam functional, which for quite some time was off due to a loose spade connector at the headlight (legacy of PO). Perhaps when I had the low beam out there remained enough current to partly charge the battery, thus masking the issue.

I scraped the connectors and applied dielectric grease and guess what- now all phase wires measure 0,5 ohms at the rectifier plug, no shorts to the ground and it charges at 13,85V +- 0,02V at 1400 to 3500 RPM (didn't go higher so I didn't disturb the neighbors). This is on the loaner no-name battery. IMO that's perfect for a shunt type rectifier. The manual asks for 14V but considering the battery wasn't 100% full and the low beam was on, I will call it within spec.

However I'm not brave enough to knowingly ride the bike any longer with that plug burned off like that.

I was extremely pissed off but now I'm so glad I didn't catch fire. I will buy a new 3 pin plug set, and also replace the rectifier with a MOSFET one as soon as I find something reasonably priced.

And I'll buy a new battery. I put the old one on the charger (0,8A/ hour) and it went to fully charged in around 5 hours, so to my estimations it's only got 3.5 to 4A.

@Motogiro
I have installed a FH020AA on another bike, and after some checking it turns out that I even have a new extra plug kit. At that time (few years ago) I also intended to replace the rectifier on the FZ6, but I couldn't find any reports of failed FZ6 OEM ones (unlike Honda rectifiers...) so I didn't think it was necessary. Now this incident certainly put a toll on the rectifier so it's certainly on the to do list.

The one I got in the past was allegedly from a low mileage BMW 1200GS, this time I will also look for a OEM one. After a quick ebay search it seems that now there are even more fakes than before, such as new FH020AA at 20 someting $ -yeah right!

Do you happen to have a pic with the FH020AA installed on the bike?
 

Attachments

  • photo_2020-05-16_14-54-57.jpg
    photo_2020-05-16_14-54-57.jpg
    120.7 KB · Views: 61

pizza_pablo

Site Supporter
Joined
Apr 28, 2020
Messages
73
Reaction score
44
Points
18
Location
PNW
Visit site
So now I need to order a stator.
Thanks, again, again, for all of the help in this!

What do I do with the extra Regulator?
Surely, I cannot return an open and used electrical part.
Try to sell here or ebay?
Retain as a spare?
 

Gary in NJ

Junior Member
Site Supporter
Joined
May 6, 2014
Messages
1,964
Reaction score
1,908
Points
113
Location
Amoungst the Twisty Roads
Visit site
You’ll probably never need a spare. You can list it here in the classified section, but you might wait a while to sell it. The FZ6 r/r is used on many Yamaha sport bikes, so if you list it on eBay, be sure to list it by part number, not as an FZ6 r/r.
 

pizza_pablo

Site Supporter
Joined
Apr 28, 2020
Messages
73
Reaction score
44
Points
18
Location
PNW
Visit site
You’ll probably never need a spare. You can list it here in the classified section, but you might wait a while to sell it. The FZ6 r/r is used on many Yamaha sport bikes, so if you list it on eBay, be sure to list it by part number, not as an FZ6 r/r.
Yes, I would definitely wait until my charging issue is solved.
Thanks!
 

Motogiro

Vrrroooooom!
Staff member
Moderator
Elite Member
Site Supporter
Joined
May 8, 2008
Messages
14,968
Reaction score
1,138
Points
113
Location
San Diego, Ca.
Visit site
@Motogiro
I have installed a FH020AA on another bike, and after some checking it turns out that I even have a new extra plug kit. At that time (few years ago) I also intended to replace the rectifier on the FZ6, but I couldn't find any reports of failed FZ6 OEM ones (unlike Honda rectifiers...) so I didn't think it was necessary. Now this incident certainly put a toll on the rectifier so it's certainly on the to do list.

The one I got in the past was allegedly from a low mileage BMW 1200GS, this time I will also look for a OEM one. After a quick ebay search it seems that now there are even more fakes than before, such as new FH020AA at 20 someting $ -yeah right!

Do you happen to have a pic with the FH020AA installed on the bike?

No, I have the Suzuki SV1000s. I have had to bypass a stator on a Honda CBR1000 that had the exact same plug burn out. I remember reading where the VFRs were having a lot of R/R failures. People were even adding aluminum to create extra heat sink for them.
Yeah all it takes is money but since I know a guy that does work on stuff like this I can justify a better R/R setup. :p:)
 
Last edited:

bigborer

Site Supporter
Joined
Feb 16, 2017
Messages
447
Reaction score
78
Points
28
Location
EU
Visit site
No, I have the Suzuki SV1000s. I have had to bypass a stator on a Honda CBR1000 that had the exact same plug burn out. I remember reading where the VFRs were having a lot of R/R failures. People were even adding aluminum to create extra heat sink for them.
Yeah all it takes is money but since I know a guy that does work on stuff like this I can justify a better R/R setup. :p:)

They did "upgrade" the Honda RRs with fins at some point in the year 200x, but they were still shit. When I installed the FH020AA on my VTR1000F it had the plug at the RR partly melted. At some time I was chatting about this with a mechanic and he swore that all those "legendary" Honda RR issues are strictly due to corroded pins adding resistance and load to the RRs.

To anyone reading:
FH020AA is MOSFET shunt style, meaning it's superior to the OEM "simple" shunt rectifier on the FZ6
SH847 is series
SH750 is also series and much cheaper and easier to find but beware that it has a rev limit of around 10k RPM so IT IS NOT SUITABLE FOR A FZ6

I have just ordered a FH027AA rectifier from a 2019 CBR500 allegedly having under 4k miles! FH027AA seems to be the newest iteration FH020AA. To my research all models that had FH020AA as OEM, after 2018 they put FH027AA as OEM. CBR500, newer Yamaha MTs and Tracers, any BMW 1200 are among good donor models for MOSFET shunt style rectifiers, as long as the of the part numbers on it begins with FH . FH = FET SHUNT, and FET = MOSFET.

Why did I not buy a series one, aka SH847 ?
1- price: It would have cost me 2-3x more (got the FH027AA for around $55 shipped)
2-size: the SH847 is larger than the FH027AA, and the FH027AA is likely already bigger than the SH719AA (OEM FZ6).
3-honestly I'm not very convinced of the benefits. Please correct me if I'm wrong but IMO as the power generation works by spinning a permanent magnet, the stator is providing full current and voltage per certain RPM as long as the engine is on, regardless of the type of rectifier. Should the series one be a few % more efficient than the MOSFET shunt, it's unlikely that this would translate to longer life for the stator or any other electrical component.


Is this a question for me?
A request for a picture of the original Regulator?
No, I was interested on a pic of a SH847 or FH020AA installed in a FZ6.
 

Gary in NJ

Junior Member
Site Supporter
Joined
May 6, 2014
Messages
1,964
Reaction score
1,908
Points
113
Location
Amoungst the Twisty Roads
Visit site

Motogiro

Vrrroooooom!
Staff member
Moderator
Elite Member
Site Supporter
Joined
May 8, 2008
Messages
14,968
Reaction score
1,138
Points
113
Location
San Diego, Ca.
Visit site
Why did I not buy a series one, aka SH847 ?
1- price: It would have cost me 2-3x more (got the FH027AA for around $55 shipped)
2-size: the SH847 is larger than the FH027AA, and the FH027AA is likely already bigger than the SH719AA (OEM FZ6).
3-honestly I'm not very convinced of the benefits. Please correct me if I'm wrong but IMO as the power generation works by spinning a permanent magnet, the stator is providing full current and voltage per certain RPM as long as the engine is on, regardless of the type of rectifier. Should the series one be a few % more efficient than the MOSFET shunt, it's unlikely that this would translate to longer life for the stator or any other electrical component.

The series type is only passing current when the voltage is below threshold. That means it is not being used as a resistive load that shunts current from the stator to ground. The stator runs cooler as well as the regulator.

I've seen Infra red photos of the heat difference with series regulation. That reduction adds to the entire engine. the benefit is there.

The shunt regulator must constantly use current from the stator and dissipate what energy that is not used for the bike/battery into the heat sink.

Easing the constant load on the stator reduces heat and and possibly hysteresis which might further alleviate additional mechanical force that could also contribute to winding insulator and physical breakdown. Motorcycle charging technology seems week when compared to automobile charging systems. There seem to be many failures on bikes in comparison and It's probably largely due to a weight saving system design. With today's solid state technology we can switch over to series and gain the benefit of long lasting, more reliable charging systems. The down side is more bucks for less heat.
 

bigborer

Site Supporter
Joined
Feb 16, 2017
Messages
447
Reaction score
78
Points
28
Location
EU
Visit site
The series type is only passing current when the voltage is below threshold. That means it is not being used as a resistive load that shunts current from the stator to ground. The stator runs cooler as well as the regulator.

I've seen Infra red photos of the heat difference with series regulation. That reduction adds to the entire engine. the benefit is there.

The shunt regulator must constantly use current from the stator and dissipate what energy that is not used for the bike/battery into the heat sink.

Easing the constant load on the stator reduces heat and and possibly hysteresis which might further alleviate additional mechanical force that could also contribute to winding insulator and physical breakdown. Motorcycle charging technology seems week when compared to automobile charging systems. There seem to be many failures on bikes in comparison and It's probably largely due to a weight saving system design. With today's solid state technology we can switch over to series and gain the benefit of long lasting, more reliable charging systems. The down side is more bucks for less heat.
I don't fully get it. :(

Imagine we have a water source, a water hose and a bucket. The bucket is the battery. A hand controls the hose, being the RR.
-shunt type means that when the bucket is full, the hand take the hose out of the bucket and makes it splash the ground. Aka the current gets shunt to the ground. Then the buckets gets empty and the hand turns the hose again to the bucket.
-series type means that when the bucket is full the hand turns off the hose

This sounds great however the way I see it the water source is STILL pumping, even with the hose off.

Please comment on my logic:
1- If the stator, basically a magneto, is spinning, it is producing AC current regardless of it being connected to a rectifier or not. Is this correct?
2-The current produced must go somewhere. Either to an electrical component such as a light bulb or turn into heat, or both. Is this correct?
3-Ohm's law states that I = V/R. So the smaller the resistance the larger the current. Now if the series one isn't acting as a resistor, doesn't this actually increase the current inside the stator? And more current = more heat? So how come the series rectifier actually decrease stator current/heat?
 

Motogiro

Vrrroooooom!
Staff member
Moderator
Elite Member
Site Supporter
Joined
May 8, 2008
Messages
14,968
Reaction score
1,138
Points
113
Location
San Diego, Ca.
Visit site
Okay here's a simple way to think of series. You have a lamp. the lamp is plugged into your AC outlet. The lamp has a switch. The switch is in series. When the switch is closed, current flows through the wires,through the bulb (work load). Outside your house is the meter that measures current. It is also in series. When the lamp switch is opened the current ceases flow through the bulb. The meter stops measuring current. The power generating plant still produces potential EMF. But the current is not being used. P = V x I
If there is no current flow there is no power use.

The shunt regulator is regulating voltage by loading the power produced so the the voltage drop occurs at a specified voltage by loading the circuit when at that voltage. Regardless, unlike the series circuit, there is current flow and the potential from power generation is constantly loaded into the shunt and released as heat. Below that specific voltage the shunt does not activate and power produced is used by the bike devices. Still the stator will be at constant load and create heat within the stator.

Yes, as the the engine is spinning the stator is producing potential but it is not being used (no current flow in series)so there is no load and less heat.
 
Last edited:

bigborer

Site Supporter
Joined
Feb 16, 2017
Messages
447
Reaction score
78
Points
28
Location
EU
Visit site
I know how series and parallel circuits work.

What confused me is that I imagined that stator produced the same output regardless of load.
Yes, as the the engine is spinning the stator is producing potential but it is not being used (no current flow in series)so there is no load and less heat.
This makes sense. Now, how would you calculate
1- the heat produced when the generator is only producing potential
2-the heat produced when the generator is at full load
?

Also, this makes me wonder:
3- for a shunt type RR is the stator heating just as much when the RR is shunting to ground vs when it's charging the battery? Or as I = V/R, R gets higher when shunting to ground so the stator heat is at least a bit reduced? E.g. low beam on vs low beam off. Is the stator cooler with the beam off?

PS: Today I tried to shop for a new stator plug but with no luck- no shop had anything that would have accepted more than 10A. Even online I can't find much. So what's left is soldering the wires directly which is kind of a bummer, firstly because the cable is so short that after cutting the plugs now there's the need to solder some extension, and secondly because if the stator ever needs to be replaced there will be extra work needed removing the tank and resoldering.
Put the battery in the trunk and on the way back I went to a battery shop and tested the old FZ6 battery- it measured at 203CCA, and the tech working at the shop said "that definitely seems still good for use". But I think I'll replace it regardless.
 

TownsendsFJR1300

2007 FZ6
Site Supporter
Joined
Feb 7, 2009
Messages
12,516
Reaction score
1,157
Points
113
Location
Cape Coral, Florida, USA
Visit site
Might look here for a new terminal end:


or here:



.
 

Motogiro

Vrrroooooom!
Staff member
Moderator
Elite Member
Site Supporter
Joined
May 8, 2008
Messages
14,968
Reaction score
1,138
Points
113
Location
San Diego, Ca.
Visit site
Yes it would be interesting to see the curve on the shunting. I imagine the current remains the same after the shunt is triggered as far as load on the stator. The shunt current would probably vary if more resource is used by the bike
I went through the same plug scenario with a burned plug assembly. It was more a time constraint as my friend wanted to ride sooner than later. The location was not bad so we opted to bypass the plug.
 
Top