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CBR929 Charging problems

11952 Views 18 Replies 4 Participants Last post by  MACI4LIFE
I'm sure this has been discussed previously somewhere on the forum but I have not found an answer yet.

My 929 seems to charge the battery fine when I am riding/touring below 7000 rpm, but when doing extended runs of an hour or more at revs around 7000 or higher the battery drains.

I have had to take a jump start a couple of times off a car, and after 20 minutes of idle the battery seems fine again. I replaced the batttery thinking it was the problem and not holding the charge, but it happened again today on a fast run after an hour. I rode for 3 hours last week under 7000 and it was fine.

I attached a power commander some time ago, and probably by chance can trace the start of this problem to around that time. The PC3 is attached to the negative battery termnal as instructed, otherwise it is a plug a play model specific for the 929. Any thoughts on the problem?

Cheers.
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To add more, I have checked the charge over the battery terminals, when the bike is running, it is around 15 volts.
Sounds like you have the notorious stator issue.
sounds more like a regulator/rectifier issue.

it could be failing when it starts overheating, or a bad ground on the RR that stops it from dissipating the extra voltage and heat. you'll have to do some searching to test the RR.

my test was just letting the bike idle for a long time and constantly monitoring the RR when it was overheating. in your case you may want to give it some revs.
Sounds like the stator is on the way out.
Check the AC voltage on each wire and that none are grounded.
Sounds like the stator is on the way out.
Check the AC voltage on each wire and that none are grounded.
Can you give me a little more info on the STATOR? What is it, where is it on the bike?
Can you give me a little more info on the STATOR? What is it, where is it on the bike?
The stator is the coil of the alternator. It's inside the left engine cover.
It has three yellow wires running to the regulator (which is under the left rear fairing).
Measure the AC voltage at each wire. They should be putting out similar voltage. Also make sure there is no continuity between any of the wires or to earth as that will indicate the stator has melted.
Cheers for this Larry. Do the stators regularly go on 929s?

If the voltage is inconsistent coming off the stator, or if the stator has earthed, will it most likely need replacing?

And a silly question, but inside the left engine cover it is dry right, no oil?

Cheers
Cheers for this Larry. Do the stators regularly go on 929s?

If the voltage is inconsistent coming off the stator, or if the stator has earthed, will it most likely need replacing?

And a silly question, but inside the left engine cover it is dry right, no oil?

Cheers
Stators and regulators die with monotonous regularity on Honda sportsbikes :)
Most likely it would need replacing although a member has posted an excellent how-to if you wanted to re-wire it yourself.
No, there is oil in there. Lean the bike to the right against a wall and very little will come out but you will need to put a pan down or a least a pile of newspaper.
It also has a gasket. If it's been glued then you'll need to buy or make another one.
I checked the AC voltage across the positive and negative terminals this evening. I do not know if this gives an accuracte reading of the voltage the bikes system is producing or not. I did not touch the battery, just the leads on and off the battery, but the battery was connected of course.

Anyway, at idle it was about 15.2 volts and at 8000rpm it was about 15.4v.

I am not sure if this is any sort of acurate reading. Any thoughts?

I think I will take it off to the shop tomorrow for them to have a look at. They will probably have to replace the ststor and RR with a used set of a scrapped bike as I'll have to order a new one from overseas.
I checked the AC voltage across the positive and negative terminals this evening. I do not know if this gives an accuracte reading of the voltage the bikes system is producing or not. I did not touch the battery, just the leads on and off the battery, but the battery was connected of course.

Anyway, at idle it was about 15.2 volts and at 8000rpm it was about 15.4v.

I am not sure if this is any sort of acurate reading. Any thoughts?

I think I will take it off to the shop tomorrow for them to have a look at. They will probably have to replace the ststor and RR with a used set of a scrapped bike as I'll have to order a new one from overseas.
That is DC voltage that has been rectified from AC by the rectifier.
The voltage coming from the stator before it reaches the rectifier is AC and should be somewhere around 50-70VAC from memory.
Your numbers are fine so it may not be breaking down until it's under load. If you attach a voltmeter to the battery terminals and mount it near the dash you can check it under load when you're riding over 7000RPM. If it doesn't drop below14.5V then it's probably not a charging fault.
Are the battery leads clean and tight?
That is DC voltage that has been rectified from AC by the rectifier.
The voltage coming from the stator before it reaches the rectifier is AC and should be somewhere around 50-70VAC from memory.
Your numbers are fine so it may not be breaking down until it's under load. If you attach a voltmeter to the battery terminals and mount it near the dash you can check it under load when you're riding over 7000RPM. If it doesn't drop below14.5V then it's probably not a charging fault.
Are the battery leads clean and tight?

A good thought, I will attach the volt meter to it tonight and take it for a spin. The leads all look clean and they are tight. cheers.
run the bike and let it get nice and hot and continue checking. you may get the voltage drops once everything gets nice and hot.
run the bike and let it get nice and hot and continue checking. you may get the voltage drops once everything gets nice and hot.

I checked the voltage again last night with the temp around 95 degrees. At idle 15.4v is produced and higher revs (8000rpm) it fluculates around 16.5v. Will too much voltage have a similar effect to not enough voltage in terms of recharging?

Your comments above seem to make sence, that it may not be causing problems until it is nice and hot. Fast runs tend to keep the bike up around 100 degrees c + in Thailand. Probably by coincidence the problem started around the time I installed the PC3. Could there be any link between the charging issues and the Power Commander?

To me it apears that there seems to be enough charge being produced, possibly the Regulator is playing up. It is at the shop for a couple of days to be checked.
the pc3 doesn't directly connect to the battery, so it probably wouldn't cause a draining issue. If it was faulty it probably would just cause the bike run really poorly or shut it off all together.

16.5 is getting a little high. it's the RR that controls the voltage. A faulty RR will either cause no voltage to go through, or not regulate the voltage properly anymore. It looks like it may not be regulating it anymore.

there is a way to test the RR, but as the saying goes; you can check to see if the RR is bad, but there's no way to test it to make sure that it's good.

you will have to do some searching on this board for the link to a website that shows you how to test the RR.

personally speaking, it sounds like the stator is working fine for now.
the pc3 doesn't directly connect to the battery, so it probably wouldn't cause a draining issue. If it was faulty it probably would just cause the bike run really poorly or shut it off all together.

16.5 is getting a little high. it's the RR that controls the voltage. A faulty RR will either cause no voltage to go through, or not regulate the voltage properly anymore. It looks like it may not be regulating it anymore.

there is a way to test the RR, but as the saying goes; you can check to see if the RR is bad, but there's no way to test it to make sure that it's good.

you will have to do some searching on this board for the link to a website that shows you how to test the RR.

personally speaking, it sounds like the stator is working fine for now.
Thanks for this feedback. I have been thinking that the voltage was a little high and figuired the stator was producing charge and the RR not doing what it should be doing. I will have the shop replace the regulator and will keep doing the trial and error thing.

I'm going away riding for two days over the weekend, so will have plenty of opportunity to test it out. I have been carrying jumper leads with me lately as well just in case. Have used them twice so far.

I'll let you all know how I get on, and thanks for all the info so far.

Cheers.
what might be a cheaper alternative would be to get a voltage meter and connect it to your battery terminals and mount it to your bike somewhere up in the cluster. that way you will be able to monitor the situation in real time and know exactly when the issue occurs. 30 bucks for a digital meter vs 100 + for a regulator.

maybe something like this.

Universal Blue LED Volt\Current voltage panel meter on eBay.ca (item 350291680465 end time 17-Dec-09 12:09:15 EST)
what might be a cheaper alternative would be to get a voltage meter and connect it to your battery terminals and mount it to your bike somewhere up in the cluster. that way you will be able to monitor the situation in real time and know exactly when the issue occurs. 30 bucks for a digital meter vs 100 + for a regulator.

maybe something like this.

Universal Blue LED Volt\Current voltage panel meter on eBay.ca (item 350291680465 end time 17-Dec-09 12:09:15 EST)

Cheers, thanks for the idea. If the problem continues I will try this.
Cheers, thanks for the idea. If the problem continues I will try this.
if you plan on keeping the bike for a while it might be a good investment for future use.
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