Voltage with Honda CM450 Rectifier?

[pmong]

Hi everyone,

Again thanks to those who provided the great advice on fixing the problem with the charging system, particularly Cliff and Tom.

I bought a used Honda CM450 R/R. Big compared to the Suzuki R/R on the GS450GA. My adult son made a special adapter plate to lower it so the side cover can fit. See links to photos below.

With the Honda R/R, we are getting the following:

Key off, slightly under 13 volts.
Key on, drops and slowly declines towards 12 volts
At or near idle, about 14 volts
At moderate rev (GS450GA does not have a tach), over 13.5 volts
At high rev, 13.9 volts.

This does not match the voltage in Mr. posplay's Quick Test PDF.

Are the above results OK? I know that there is an additional wire from the R/R, which we attached to the orange wire. My understanding is that senses the load in the switched electrical components. Is that related to the voltage pattern I see above?

Also, with the key off, there is slight discharge when I place the VOM meter between the battery and bike. (0.2 or 0.02 volt).

Thanks in advance for your help.

http://i194.photobucket.com/albums/z45/pmong9/RRAdapter-1.jpg
http://i194.photobucket.com/albums/z45/pmong9/RRAdapter-2.jpg
http://i194.photobucket.com/albums/z45/pmong9/RRAdapter-3.jpg
http://i194.photobucket.com/albums/z45/pmong9/RRAdapter-4.jpg

 

[Steve]

Voltages sound good to me. :clap: :clap:

Not all regulators will hit the "perfect" 14.4 volts. Yours appears to be set at 14.0.

As it gets to the regulation setpoint, the voltage will lower just a bit, due to the way it regulates.
As engine speed increases, it has to regulate more, but the ignition demands more, so the voltage will be just a little less.

Technically, anything over 12.6 volts will charge the battery, the question is "how quickly".

.

 

[argonsagas]

Hi everyone,

Again thanks to those who provided the great advice on fixing the problem with the charging system, particularly Cliff and Tom.

I bought a used Honda CM450 R/R. Big compared to the Suzuki R/R on the GS450GA. My adult son made a special adapter plate to lower it so the side cover can fit. See links to photos below.

With the Honda R/R, we are getting the following:

Key off, slightly under 13 volts.
Key on, drops and slowly declines towards 12 volts
At or near idle, about 14 volts
At moderate rev (GS450GA does not have a tach), over 13.5 volts
At high rev, 13.9 volts.

This does not match the voltage in Mr. posplay's Quick Test PDF.

Are the above results OK? I know that there is an additional wire from the R/R, which we attached to the orange wire. My understanding is that senses the load in the switched electrical components. Is that related to the voltage pattern I see above?

Also, with the key off, there is slight discharge when I place the VOM meter between the battery and bike. (0.2 or 0.02 volt).

Thanks in advance for your help.http://i194.photobucket.com/albums/z45/pmong9/RRAdapter-1.jpg
http://i194.photobucket.com/albums/z45/pmong9/RRAdapter-2.jpg
http://i194.photobucket.com/albums/z45/pmong9/RRAdapter-3.jpg
http://i194.photobucket.com/albums/z45/pmong9/RRAdapter-4.jpg

There should not be any discharge when the key is off, but you may getg a difference if the check is done very shortly after charging stops as it takes a few minutes for the battery voltage to stabilize and some drop is normal.

The voltages you are getting are fine.

 

[Nessism]

Did you bypass the factory wiring and feed the stator wires directly into the R/R? Make a good ground path for the R/R? How does power get from the R/R to the battery?

Asking because the voltage seems a little low. Best to see 14.5 volts or so. You might have voltage loss in the wiring.

 

[pmong]

Thanks.

Agree that anything over a certain voltage indicates some charging. The output is certainly over 13 volts across the revs. Just not getting over 14 volts at higher revs. Strange.

Voltages sound good to me. :clap: :clap:

Not all regulators will hit the "perfect" 14.4 volts. Yours appears to be set at 14.0.

As it gets to the regulation setpoint, the voltage will lower just a bit, due to the way it regulates.
As engine speed increases, it has to regulate more, but the ignition demands more, so the voltage will be just a little less.

Technically, anything over 12.6 volts will charge the battery, the question is "how quickly".

.

 

[pmong]

Yes, did look at the voltage after charging. I will test again tomorrow before starting her up.

There should not be any discharge when the key is off, but you may getg a difference if the check is done very shortly after charging stops as it takes a few minutes for the battery voltage to stabilize and some drop is normal.

The voltages you are getting are fine.

 

[pmong]

I directly connected the three stator wires directly to the R/R and not through the factory wires. The Honda is a six wire R/R. I wired the green and red to the factory wires that are directly connected to the battery, and black to a switched (orange) wire as recommended.

I think I will go back and clean the connections. Did that with some but not all connections because it was getting dark and don't have a garage.

Thanks for the suggestions. Will see if the cleaning makes a difference.

The no load AC voltage appears to be right. I did get a new stator because I am redoing the whole system, but the gasket has not yet arrived.

Did you bypass the factory wiring and feed the stator wires directly into the R/R? Make a good ground path for the R/R? How does power get from the R/R to the battery?

Asking because the voltage seems a little low. Best to see 14.5 volts or so. You might have voltage loss in the wiring.

 

[posplayr]

Hi everyone,

With the Honda R/R, we are getting the following:

Key off, slightly under 13 volts.
Key on, drops and slowly declines towards 12 volts
At or near idle, about 14 volts
At moderate rev (GS450GA does not have a tach), over 13.5 volts
At high rev, 13.9 volts.

Not sure if your "Key on" going to 12V is really all the way down to 12V?? If it went from 13V to 12.5V that would indicated a good battery. 13V down to 12V would indicate a weak battery.

14V at idle seems high but more strange than a problem.
The progression from 13.5V to 13.9V as you increase RPM is good. It could be low if your battery is poor (e.g. 12.0V with the key on). The first part of the test is not really clear.

It seems you have a decent battery and are charging, as stated plainly in the Quick Test thread this is more of a sanity test and I would still do at least the Phase A tests where you measure voltage drops between the R/R(+) and battery (+) (do minus as well) to see how much voltage drop you get at 5K rpm.

Since this is a 6 wire R/R I would measure voltage difference between battery (+) and the sense point.

 

[Suzuki_Don]

I am using the same unit on my 550 and have the sense wire connected to the battery positive and the bike is on a "tender" when I am not using it. This works for me.

 

[tom203]

Thanks.

Agree that anything over a certain voltage indicates some charging. The output is certainly over 13 volts across the revs. Just not getting over 14 volts at higher revs. Strange.

Anything over 13.2 is charging battery. My Shindengen R/R holds steady at 14 volts from about 1800 rpm to past 6000 according to dash voltmeter. Another unit would likely be slightly different.You're good to go!

 

[pmong]

From "Key off" to "Key on", the voltage dropped by about a half volt. It is a new battery, so I assume that it is good, or at least hope so. I guess my concern was the higher voltage at lower rpm, but if it is charging, then that is good. Hope to tinker a little this weekend with cleaning the connections and a couple more tests.

Thanks.

Not sure if your "Key on" going to 12V is really all the way down to 12V?? If it went from 13V to 12.5V that would indicated a good battery. 13V down to 12V would indicate a weak battery.

14V at idle seems high but more strange than a problem.
The progression from 13.5V to 13.9V as you increase RPM is good. It could be low if your battery is poor (e.g. 12.0V with the key on). The first part of the test is not really clear.

It seems you have a decent battery and are charging, as stated plainly in the Quick Test thread this is more of a sanity test and I would still do at least the Phase A tests where you measure voltage drops between the R/R(+) and battery (+) (do minus as well) to see how much voltage drop you get at 5K rpm.

Since this is a 6 wire R/R I would measure voltage difference between battery (+) and the sense point.

 

[pmong]

Thanks for the feedback. My son made wiring harness for a "tender", and I now just need an extension cord to run from the house to the bike. I am ok with connecting the Honda black wire to the orange Suzuki wire for now.

I am using the same unit on my 550 and have the sense wire connected to the battery positive and the bike is on a "tender" when I am not using it. This works for me.

 

[pmong]

Thanks. The output is nearly 14 volts at higher revs (13.9) and steady. It could be that my cheap VOM meter (Harbor Freight) is reading slightly low. Will see this weekend how well the charging system works. Plan to go on a ride with my son, and we have bike towing service through AAA. Recently got a GZ250 for my son to ride rather than his Vespa. He wants something bigger, like a Triumph Bonneville, but I figure that it is better for him to get some miles on a starter bike.

Anything over 13.2 is charging battery. My Shindengen R/R holds steady at 14 volts from about 1800 rpm to past 6000 according to dash voltmeter. Another unit would likely be slightly different.You're good to go!

 

[posplayr]

From "Key off" to "Key on", the voltage dropped by about a half volt. It is a new battery, so I assume that it is good, or at least hope so. I guess my concern was the higher voltage at lower rpm, but if it is charging, then that is good. Hope to tinker a little this weekend with cleaning the connections and a couple more tests.

Thanks.

Sounds like the stator and R/R are fully functional but perhaps you have some dirt connections (on the ground side) that are not allowing the voltage to go a little higher. Typical outputs are 14.25-14.5V.

It is worth checking ; connections should be below about 0.2V voltage drop at 5000 RPM (full load)

Stock GS are as high as 15.5V but that is very sloppy.

 

[pmong]

Thanks posplayr. You have been a major resource on this issue.

Will clean the connections this weekend.

Sounds like the stator and R/R are fully functional but perhaps you have some dirt connections (on the ground side) that are not allowing the voltage to go a little higher. Typical outputs are 14.25-14.5V.

It is worth checking ; connections should be below about 0.2V voltage drop at 5000 RPM (full load)

Stock GS are as high as 15.5V but that is very sloppy.