Charging system issue

[p.dath]

My motorcycle has started having troubles starting when cold in the morning. It starts ok at other times.

The battery is 18 months old. The other day I took the battery out, put it on a trickle charge fo a day, and then put it back in. It went fine for a couple of days, and then again wouldn't start in the morning.

So I decided to check the charging system. I've checked the stator, and are reasonably confident it is giving all the correct readings.

However I am not so confident about the regulator/rectifier. At the moment the bike is starting ok. The battery volate when off is 12.8V. I've checked for leak current, and there is none. When I start the bike and start increasing the revs the volatge across the battery starts increasing.

By the time I get to 5000 RPM the volatge across the battery is up to 17V. I think this is too high. I haven't tried revving any higher, as I suspect the volatge will keep going up. My understanding is the regulator/rectifier should be holding the voltage at a constant level.

So do you think my regulator/rectifier is poked?

ps. This is a 1999 Honda CBR600F4.

[gammaguy]

yup.its poked

[Macontour]

The battery may be just getting old, even though it is only 18 months old. Try starting it after charging with a load(ie the lights on) and see what happens. If it won't crank, the battery is stuffed. You could also get a load test done on it by an auto sparky.

17 volts sounds a little high to me, I would have thought that somewhere around 13.5 would be more likely. Too high a voltage will boil your battery dry and kill it that way.

[FJRider]

So do you think my regulator/rectifier is poked?

ps. This is a 1999 Honda CBR600F4.

I would say it might be.

AND .... it most likely poked the battery too ...

Cold weather (usually) brings out the true state of batterys

[spanner spinner]

sealed batteries like the one fitted to your bike don't like overvoltage so the faulty reg/rec will have damaged it. Fit a new reg/rec and a new battery and the problem will go away. the best rec/rec unit to replace the standard unit is a Shindengen MOSFET regulator/rectifier (google it) these don't suffer from early burn out like the standard units do.

[tigertim20]

My motorcycle has started having troubles starting when cold in the morning. It starts ok at other times.

The battery is 18 months old. The other day I took the battery out, put it on a trickle charge fo a day, and then put it back in. It went fine for a couple of days, and then again wouldn't start in the morning.

So I decided to check the charging system. I've checked the stator, and are reasonably confident it is giving all the correct readings.

However I am not so confident about the regulator/rectifier. At the moment the bike is starting ok. The battery volate when off is 12.8V. I've checked for leak current, and there is none. When I start the bike and start increasing the revs the volatge across the battery starts increasing.

By the time I get to 5000 RPM the volatge across the battery is up to 17V. I think this is too high. I haven't tried revving any higher, as I suspect the volatge will keep going up. My understanding is the regulator/rectifier should be holding the voltage at a constant level.

So do you think my regulator/rectifier is poked?

ps. This is a 1999 Honda CBR600F4.
yes your regulator is fucked, at 5k rpm, it should give out about 14V across the battery, and shouldnt ever be any more than that. Your regulator is over charging your battery, which is also fucking your battery.
Replace both the regulator and the battery together, and you should be away without any problems - this is a common issue on the older CBR600's, by older I mean the whole F series (thought the F4i might be exempt from this blanket statement?) I had the same issue on my F2, replaced regulator and battery, problems gone.

[Fast Eddie]

yea i burnt out a regulator and 2 cdis during my 600F1 ownership..

nice bikes tho

[tigertim20]

yea i burnt out a regulator and 2 cdis during my 600F1 ownership..

nice bikes tho

they are awesome bikes! pretty much every Honda of the era had the same/similar issues, the earlier (circa 1998) VFR800s were particularly bad for it.
You have had the same on your blade too just recently havent you?

[Fast Eddie]

they are awesome bikes! pretty much every Honda of the era had the same/similar issues, the earlier (circa 1998) VFR800s were particularly bad for it.
You have had the same on your blade too just recently havent you?

too right I did.. and then the mrs GN250 shortly after ;)

know all about the charging system now haha.

[p.dath]

The battery may be just getting old, even though it is only 18 months old. Try starting it after charging with a load(ie the lights on) and see what happens. If it won't crank, the battery is stuffed. You could also get a load test done on it by an auto sparky.

I left it on a trickle charger for a couple of days. I can't turn the headlight off ... It starts ok at the moment. I'll have to try it again after getting a new regulator (due in on Monday), and see how it goes in the cold. Otherwise I'll be replacing the battery.


sealed batteries like the one fitted to your bike don't like overvoltage so the faulty reg/rec will have damaged it. Fit a new reg/rec and a new battery and the problem will go away. the best rec/rec unit to replace the standard unit is a Shindengen MOSFET regulator/rectifier (google it) these don't suffer from early burn out like the standard units do.

Alas I need the bike going again. After ringing around all the Honda dealers on Saturday to see if anyone had anything in stock of anything (and they all had nothing) I've ordered in a genuine Honda one (mostly because they can have it to me by Monday). The version coming off my bike is version "0", and the new one is version 10 ... so they might have improved it.

[spanner spinner]

the version 10 will be slightly better than what was on the bike but they still fail, usall last about 50000km.

[p.dath]

the version 10 will be slightly better than what was on the bike but they still fail, usall last about 50000km.

Thanks for the tip. I'm kinda thinking about selling the bike and getting another one at the moment.

I'm starting to look back at what I spent on maintenance over the last 12 months, and it's adding up quite a bit. Rather than pooring more money into maintaining an older bike I'm starting to think it might be time to make a jump and get another bike less than 10 years old.

[CookMySock]

By the time I get to 5000 RPM the volatge across the battery is up to 17V.There is no way a battery can shift voltage that far unless you are pushing hundreds of amps into it, OR the batterys' internal resistance is wayyy too high, ie buggered. Clearly we're looking at the latter in this case. <_<

Are you sure its not just low on electrolyte?

[FJRider]

... The version coming off my bike is version "0", and the new one is version 10 ... so they might have improved it.

If your luck is the same as mine ... all the plugs/connecters will be different, as will be the colour of the wires. And all wires will be be long enough to reach all possibe connection points. :facepalm:

[p.dath]

There is no way a battery can shift voltage that far unless you are pushing hundreds of amps into it, OR the batterys' internal resistance is wayyy too high, ie buggered. Clearly we're looking at the latter in this case. <_<

Are you sure its not just low on electrolyte?

It's a sealed battery ...


If your luck is the same as mine ... all the plugs/connecters will be different, as will be the colour of the wires. And all wires will be be long enough to reach all possibe connection points. :facepalm:

The conenctors were identical. I bolted it back into place last night, plugged it in, and gave it a test.


The results were interesting. As soon as I take the bike off idle (aka rev the engine) it sits around 14V - and it is nice and stable now. At idle the voltage is actually a bit higher, and less stable (aka the volatge wanders up and down a little bit). I also have heated grips. I notice at idle now when the grips are on the headlight now flickers a tiny bit.

I might try turning the idle up a tiny bit. Then again, it doesn't both me that much so I'll probably just leave it. :)

[sinfull]

yea i burnt out a regulator and 2 cdis during my 600F1 ownership..

nice bikes tho
Wot he said, ya lucky ya didn't burn out ya CDI

[Akzle]

yes your regulator is fucked, at 5k rpm, it should give out about 14V across the battery, and shouldnt ever be any more than that. Your regulator is over charging your battery, which is also fucking your battery.
Replace both the regulator and the battery together, and you should be away without any problems - this is a common issue on the older CBR600's, by older I mean the whole F series (thought the F4i might be exempt from this blanket statement?) I had the same issue on my F2, replaced regulator and battery, problems gone.+1

14.8V is the MAX that should go into a 12v battery and cranking batteries should not go below 10.4 V.
at 17v your battery is getting nearly 3v per cell, which is nearly 1V over per cell. at that voltage you'll be overheating your battery, if you recall school C science, higher heat in a conductor creates greater resistance, which in turn will draw higher current, which creates more heat.
IF the plates in your battery aren't stuffed you'll get away wihtout a new one. if it's SLA (sealed lead acid) replace it.
if you can then maybe some INOX, a desulphation charging cycle and then clean water in the cells.

generalrule for charging all batteries is half a volt over per cell.

[tigertim20]

It's a sealed battery ...



The conenctors were identical. I bolted it back into place last night, plugged it in, and gave it a test.


The results were interesting. As soon as I take the bike off idle (aka rev the engine) it sits around 14V - and it is nice and stable now. At idle the voltage is actually a bit higher, and less stable (aka the volatge wanders up and down a little bit). I also have heated grips. I notice at idle now when the grips are on the headlight now flickers a tiny bit.

I might try turning the idle up a tiny bit. Then again, it doesn't both me that much so I'll probably just leave it. :)

so wait, at idle, the voltage is higher than 14, then it DROPS to 14 when its revved?
if so I would be thinking about pulling the stator out and taking a good look at it, because that dont sound right to me.
my personal (and admittedly, not particularly huge) experience of charging systems is that they can be a cunt to correctly diagnose, because one faulty component tends to have an affect on others, e.g., a shagged stator will hurt your regulator, and a shagged regulator will fuck your battery.

Do some extra checks, or you be replacing the whole lot again in 3 months

[p.dath]

so wait, at idle, the voltage is higher than 14, then it DROPS to 14 when its revved?


Correct. Already checked the stator. The resistance of each coil is around 0.1 Ohm (which is what the service manual says it should be). Also checked for shorts to earth. All looks good.

[tigertim20]

Correct. Already checked the stator. The resistance of each coil is around 0.1 Ohm (which is what the service manual says it should be). Also checked for shorts to earth. All looks good.

did you start the bike, and unplug the stator from the regulator, and test it on A/C as well? you want to be checking the outputl. You want to test it across all combinations there are three i think, you test 1 and 2 together, 2 and 3 together, and 3 and 1 together, make sure they are all equal.

[tigertim20]

addition to above, do this wile running obviously.

[CookMySock]

Have a look at how the stator is wired and see what you can test with the engine running. Obviously you will need to be quite careful doing this, especially insulation checks to ground.