electrical bike problems

[greg]

further to my other threads I thought I'd consolidate my problems and progress so far:

back story (when the problem first started)
- fitted a new exhaust
- at the same time fiddled with my tail tidy, unplugging it all and putting it back together
- noticed loose bolt in sub frame near rectifier
- first up bike a few times at various stages, at one point i may have knocked it into gear with the side stand down, thus cutting poer
- after this bike refused to stay n when i changed into gear until i disconnected the battery for 15 mins
- went for a bike ride
- warning light came on as i was riding (a few overtakes and twisties), error 46, charging problem, bike wouldn't start, battery dead
- bump started it but it died again
- recovered vehicle back to my house

2 weeks later:
- charged battery
- checked connections
- swapped rectifier for a spare one
- tighted sub frame bolt
- fitted luggage rack
- checked for bad earthing on tail lights
- checked all other connectors were intact
- check battery voltage whilst running, was getting between 13 and 14V from idle to 5k
- went for a short ride, bike felt a tiny bit hesitant (in retrospect perhaps it wasn't getting enough power?)
- went for a long ride the next day, no problems bike was smooth

1 week later
- went for 2-3 hour ride again no problems
- next day (today), went for ride to bike shop, (1hr away), again no problems
- put tomtom on bike (small voltage drain perhaps?)
- rode from shop to home, half an hour later i felt it starting to die, pulled into a layby, and it had already stopped
- checked all connectors but they looked ok
- when trying to start it it made a clicking noise, and the display reset and fuel pumps reprimed (because of low power or a short?)

now the bike is in the garage and awaiting my attention

possible causes
1) short circuit/voltage drain somewhere
2) bad rectifier (unlikely both of them are broken?)
3) bad stator
4) improperly seated connector
5) bike not charging when revved too high (is this possible?)
6) something else?


any questions or suggestions please post them

I can't see any obvious problems with any of the connectors, and the bike hasn't seen rain for a couple of months. It might be worth attacking them with some wd40, however if this is an intermittent problem i'd rather find the exact cause, otherwise I will lose faith and trust in my bike.

 

[Morrisey]

Feel sorry for you mate -there's nothing worse than that sort of intermittent leccy problem. Surely the fault has to lie in the tail tidy or a part that you have re-fitted, possibly trapping a wire?

 

[greg]

Feel sorry for you mate -there's nothing worse than that sort of intermittent leccy problem. Surely the fault has to lie in the tail tidy or a part that you have re-fitted, possibly trapping a wire?

no, it definitely seems to check out ok


anyway, I seem to have made some progress

followed the troubleshooting guide in my haynes, and measured the resistance of my stator coil. I was getting 0.7ohms across each connection, and also the same to the earth (!). It's supposed to be about 0.34ohm, and shouldn't be earthing. Took my stator apart and it looks like one of the coils burnt out.

Now the question is whether I caused this, or whether it happened by itself. I don't want to replace it and then have it break again.

Tomorrow once the battery is charged I'm going to use the ammeter and check for current leak

QUESTION: will an R6 stator fit the FZ6 (2006 model)?
edit: looking at the part number suggests they should, R6=5SL-81410-00-00, FZ6=5VX-81410-00-00

 

[Shamus McFeeley]

Those kind of stators don't fail often, but when they do it can be because of a few different things. Your rectifier might have been the problem if it was loose for awhile. Electrical components don't like the combination of shock/vibration/heat. If your rectifier was bouncing around back there, it may have shorted it internally which also burned up your stator. Your manual should have some tests for the rectifier as well, I would test it to make sure that it is still ok. It doesn't sound to me like you were overloading the charging system, and if you checked your grounds, then there is always the chance that this was a freak occurrence and no matter what you did to your bike, that stators time was up.

I think that even though you swapped rectifiers after your initial problem, the damage to the stator was already done. With one winding gone, the stator was not able to keep up with its normal output.

 

[DownrangeFuture]

Well, the stator doesn't look too bad actually. For you to see charring on just one coil in the stator it'd be a problem with that particular coil. Like a short in that coil. And components like coils don't really get affected by heat that much. I've seen rotors/stators where the whole thing was charred black and they still worked fine.

It might have been caused by a temporary short somewhere else in the system putting an extra load.

The short to ground shouldn't be happening. That's something to chase down because it might be your culprit in the burning problem. Really as long as current will flow through the stator, the rotating magnets should be able to induce current in the stator. A short to ground might cause a condition where there isn't any current flow and so no magnetic field and therefore no AC current generated.

Stators (inductors) are hard to check with a multimeter. Generally, as long as they're not open (infinite ohms) they should work, although the current might be reduced a bit. I doubt going up .4 ohms would make that much of a difference. Not that I'm looking at the tolerances now, but I would imagine the range is like 0-5 ohms. The only real way to check is to apply an AC current to the coils and see on a Huntron or oscilloscope if the coils act like a capacitor. Not really feasible for the garage mechanic as they wont have an o-scope and 115VAC from the wall would fry this coil.

Really the way to tell where the problem is, is to add an ammeter to the circuit (two actually) and see if draw exceeds supply. If supply doesn't match what the alternator can do, then it's the alternator, otherwise you have a drain somewhere. Like a weird ground you shouldn't have in the alternator...

I wouldn't put too much stock in part numbers. In the radar I worked on, a TX-DLR51, or some such, was a 10 ohm 1/4watt resistor. A TX-DLR52 was a 1.2 farad capacitor. I needed the resistor and typo-ed and got a cap. Not that all companies are that retarded with part numbers, but even a 1mm difference here could cause a problem.

It'd be cool if the did work though.

 

[greg]

not sure if it's clear from the above but the stator is shorting out on itself, resistance from the 3 wires to the stator cover is 0.7ohm, it's supposed to be infinite. I guess the burned out coil is shorting out with the cover. I tested this with it removed from the bike.

Going to look at it now, and also check if there's a current leak anywhere.

Note that my multimeter may not be entirely accurate, but it's a good ballpark figure.

I've also ordered a replacement stator from an R6, which should hopefully be an identical replacement, but I need to be sure it won't burn out again.


measured the voltage across the three terminals, and only seemed to be getting power across one of them

one other problem i had today, my multimeter didn't seem to want to measure any amperage, so i couldn't check for a current leak :S

 

[greg]

update:

couldn't get an amps reading with the bike off (good i presume)
with the switch turned on, engine off, I read about 2-4 amps, which seemed about right to me (highest when fuel pump was priming)

I did have one question though after some light googling, somebody said their FZ1 kept destroying stators, as oil wasn't getting in there to keep it cool. Is the FZ6 stator also oil cooled? Should it be bathing in oil, or just have a bit in there?

I'm just trying to work out why mine failed, and if it was related to my exhaust change.

 

[FinalImpact]

I agree that just because it has color doesn't mean its bad.

Greg, does your OHM meter have a 'relative" setting or Zero option? Meaning, if you short the two probes together and read the value it could easily say 0.7ohms. That is the resistance of the probe wires themselves. Either subtract that number from the coil reading or use the Zero or relative function to exclude it from the measured value.

If you look at the wire size of the stator, its unlikely you opened or burned a wire. Its more likely something struck the wire and damaged it shorting it to itself. Look for missing chunks from the coating.

FWIW: Stators I've seen cooked were cause by system shorts which basically took DC current from the battery and energized the coils until they burned up. Perhaps your bad rectifier played a roll in this.

Have you found any burned wires, squished wires, frayed insulation, open fuses or anything like that?

 

[greg]

I agree that just because it has color doesn't mean its bad.

Greg, does your OHM meter have a 'relative" setting or Zero option? Meaning, if you short the two probes together and read the value it could easily say 0.7ohms. That is the resistance of the probe wires themselves. Either subtract that number from the coil reading or use the Zero or relative function to exclude it from the measured value.

If you look at the wire size of the stator, its unlikely you opened or burned a wire. Its more likely something struck the wire and damaged it shorting it to itself. Look for missing chunks from the coating.

FWIW: Stators I've seen cooked were cause by system shorts which basically took DC current from the battery and energized the coils until they burned up. Perhaps your bad rectifier played a roll in this.

Have you found any burned wires, squished wires, frayed insulation, open fuses or anything like that?

Nope nothing. Only think I can think of is my rear indicator didn't flash properly until I nudged it, kind of like it had a loose connection. All the wires and connectors seem fine.

I did fire up the bike and measure the output from the stator. I was getting almost 0V between two of the connections, and 30V from one of the others at idle, I can't remember what the third one was like but I think it was 0 also.

 

[Motogiro]

If you had a regulator problem it may have gone do to a dead short and that's what the stator was looking at and failed. The regulator/rectifier functions as a rectifier turning positive and negative potential from the stator to direct current. The stator operates differently from an alternator in that there is no regulated field. This basically means that the stator is always on output as long as the rotor with magnets is spinning. The design of the regulator part of the circuit loads the stator current down, when the charge on the system reaches it's target capacity. This loading is turned into heat and dissipated through the R/R heat sink.
It's actually a pretty interesting design considering the difference between a bike and car's requirements. The bike requires lighter weight components and doesn't required the same current usage hence a different lightweight design.

Check your R/R plug and make sure the pins look clean and are not heat discolored/damaged.

 

[greg]

Check your R/R plug and make sure the pins look clean and are not heat discolored/damaged.

yeah they looked fine

i am wondering if i need to buy a 3rd rectifier now, or if my stator was able to maintain battery charge for a couple of hundred miles

 

[Motogiro]

yeah they looked fine

i am wondering if i need to buy a 3rd rectifier now, or if my stator was able to maintain battery charge for a couple of hundred miles

Cool! I wouldn't assume the R/R has a problem. Replace your stator if it is bad and resume testing.

 

[greg]

finally got around to fitting my new stator, but I managed to strip one of the bolts holding the wire cover on inside as it was so tightly done up

Need to figure out how to get that off so I can fit my new one

 

[greg]

update:
took the cover to my local garage, and he had to drill the bolt out, as it was well threadlockd in and i'd stripped the screw, at least it only cost £20 to get done

next problem, the stator I bought was from an R6, the model numbers indicate that it should be identical, however the screw holes are slightly different, and so it doesn't fit

also sliced my hand open trying to get the bolts holding the stator off, and ended up with a trip to A&E :S

 

[greg]

now it seems like i can't find a replacement stator online, might have a go at rewinding mine tomorrow :S

any tips? what guage wire should I use?

 

[gpostarmy]

Greg, my friend I find my self feeling truly bad for you. I am glad to read that you have an idea about electrical systems and I am sure that you will resolve the issue with your bike. However, your luck seems to be operating at a substandard level. Grab yourself a horse shoe, a rabbits foot, a four leaf clover, knock on some wood, and have another go at it.

 

[rypsis]

Can you replace the individual coils or do you have to replace the entire stator assembly? Google found a few places where you can buy the entire assembly, but for quite a hefty price


From the UK:

http://www.yamahascooterspares.co.uk/spares/partImage.asp?GPN=Z:[]=69655555

Or USA

OEM Parts Yamaha FZ-6 (FZS6VC) 2006 GENERATOR - Cheap Cycle Parts

Can't believe the price though.

 

[Motogiro]

Why are you replacing all these parts? Have you established they are at fault?

 

[rypsis]

Why are you replacing all these parts? Have you established they are at fault?

There is probably something wrong with the stator, if he indeed is getting around 0.7 ohms between ground and the stator connector pins?

 

[greg]

I've only replaced the r/r so far.

I'm currently in the middle of rewinding my stator, started it yesterday but didn't put them on tight enough so couldn't finish fitting it all on. Watched a video of how they do out in the factories and it's going much better now, although slower. Yamaha wired it quite weirdly, so I am winding it the normal way which is also the same as the r6 stator.

Can't test it until next weekend as I am in amsterdam now. Found the ground fault, one of the wires had burnt through to the metal core

For reference each coil has 24-25 windings, and is 18awg gauge wire.