Am I Over-Charging

[Guest]

After having just done a restoration on my GS550 I took the bike for a 30 mile ride yesterday afternoon after work. When I first got on the road I noticed that the volt meter was charging at 14.9v, when I stopped at traffic lights and the motor was idling it was reading some where around 13.2v. And even at the end of the 30 mile ride just before pulling into my driveway it was still charging at 14.8, 14.9v. The only time the voltage dropped was when the bike was at a stand still, whenever it got up to any speed at all it was charging at the higher rate.

Some background is that I have fitted a Honda R/R from Duanage and have the sense wire connected to the rear brake light. There is no voltage drop at the brake light switch as the electrics have had a complete overhaul, clean connections, suspect lengths of wire replaced, kill switch and light switch contacts cleaned, new ignition switch, etc.

When I arrived home after the 30 mile trip and turned the motor off the battery voltage was reading 13.0v on the voltmeter that is permanently attached to the bike.

Another point of interest is the charging voltage (14.9v) did not alter whether I had the headlight ON or OFF.

I also have a gel type battery that is new.

Is the R/R overcharging?

Do I have any need to worry?

I am going on a 100 mile bike ride with some other club members on Saturday and don't want any thing to go wrong.

[posplayr]

After having just done a restoration on my GS550 I took the bike for a 30 mile ride yesterday afternoon after work. When I first got on the road I noticed that the volt meter was charging at 14.9v, when I stopped at traffic lights and the motor was idling it was reading some where around 13.2v. And even at the end of the 30 mile ride just before pulling into my driveway it was still charging at 14.8, 14.9v. The only time the voltage dropped was when the bike was at a stand still, whenever it got up to any speed at all it was charging at the higher rate.

Some background is that I have fitted a Honda R/R from Duanage and have the sense wire connected to the rear brake light. There is no voltage drop at the brake light switch as the electrics have had a complete overhaul, clean connections, suspect lengths of wire replaced, kill switch and light switch contacts cleaned, new ignition switch, etc.

When I arrived home after the 30 mile trip and turned the motor off the battery voltage was reading 13.0v on the voltmeter that is permanently attached to the bike.

Another point of interest is the charging voltage (14.9v) did not alter whether I had the headlight ON or OFF.

I also have a gel type battery that is new.

Is the R/R overcharging?

Don,

sounds high.

What is the voltage difference between the R/R sense point (at the brake light) and the battery voltage at (+)? I'm guessing the brake light is lower by about 0.4V

If the brake light sense point is low , you need to move the sense point. The output of a relay is best. Try the coil relay mod and use that. It has been discussed here many time.

Jim

[Suzuki_Don]

Don,

sounds high.

What is the voltage difference between the R/R sense point (at the brake light) and the battery voltage at (+)? I'm guessing the brake light is lower by about 0.4V

If the brake light sense point is low , you need to move the sense point. The output of a relay is best. Try the coil relay mod and use that. It has been discussed here many time.

Jim

Thanks Jim, I did check the brake light switch voltage when reassemblying the bike, wiring, etc. maybe it has altered since then. I know about the relay mod to get a full 12v at the switch, just needed some direction on the best testing to do to move forward to the next step.

BTW I have not done the coil relay mod as I had a full 12v at the coils as well when it was tested towards the end of the restoration. Maybe I had better test the coil voltage again as well.

What will be the result if I just disconnect the sense wire from the rear brake light switch? Will the R/R stop charging altogether or will it charge at maximum output -- 15+v? Just asking in case I run into trouble on the ride on Saturday and can disconnect things just to get home? Battery should have enough in it to power ignition only to get me home?

Thanks.

[rustybronco]

Don, it's too high for my tastes. although I've seen some R/R's 'high limit' regulation listed as high as 15.1V.

my simple test is to move the sense wire to the battery, start it, then see if the regulated voltage differs from where it was originally connected.

[Suzuki_Don]

Don, it's too high for my tastes. although I've seen some R/R's 'high limit' regulation listed as high as 15.1V.

my simple test is to move the sense wire to the battery, start it, then see if the regulated voltage differs from where it was originally connected.

Thanks, that is what I am after a quick test to check things out.

Thanks.

[bonanzadave]

I did the relay mod for my sense wire. I was at about 15.1 before. Now Im at a steady 14.5. I can honestly say, while I watch my on board Volt meter, that as the temp goes up so does my charging voltage. 60 degree day 14.5. 90 degree day 14.9.

[rustybronco]

Warning... if your battery negative and the R/R grounds are not at the same voltage potential, she's going to regulate higher also. that method only works if the grounds are proper. (I use a jumper cable on the negative's to prove out that side when I'm too lazy)

[Suzuki_Don]

I did the relay mod for my sense wire. I was at about 15.1 before. Now Im at a steady 14.5. I can honestly say, while I watch my on board Volt meter, that as the temp goes up so does my charging voltage. 60 degree day 14.5. 90 degree day 14.9.

Dave before I did the restoration I had mounted a relay specifically for the sense wire and switched by the brake light voltage. But since then have upgraded from one in-line fuse to a six fuse setup powering all different accessories (blinkers, horn, ignition, etc) on the bike, so the space where the relay was no longer exists and there is little to no room under the tank anymore.

I might just connect the sense wire to a switched fuse in the new panel I fitted. That way the 12v would be going from the battery (solenoid) to the main fuse then through red wire to ign switch then back on orange wire to a switched fuse. As these are all new wires and a gauge heavier than standard (did that when I revamped my wiring harness) there would be a full 12v at that switched fuse. That should get me out of trouble without fitting a relay.

[Steve]

When you say the sense wire is connected at the rear brake light, which side of the switch are you connected to?

If you are on the 'dead' side of the switch, it's the same as not having it connected, as it won't 'see' any reference voltage until you step on the brake pedal.

As others have suggested, move the wire to the battery, at least temporarily, to see if it makes a difference. I have seen more than one case where the sense wire was connected to the tail light wire, and it was overcharging because the connectors that fed the tail light and, therefore, the sense wire, were dirty, not letting the sense wire 'see' enough voltage. When the connectors were cleaned, the output voltage came right down to where it should be.

.

[posplayr]

What will be the result if I just disconnect the sense wire from the rear brake light switch? Will the R/R stop charging altogether or will it charge at maximum output -- 15+v?
Thanks.

R/R will not regulate and put full power to the electrical.

If all else fails hook direct to the battery.

[Suzuki_Don]

When you say the sense wire is connected at the rear brake light, which side of the switch are you connected to?

If you are on the 'dead' side of the switch, it's the same as not having it connected, as it won't 'see' any reference voltage until you step on the brake pedal.

As others have suggested, move the wire to the battery, at least temporarily, to see if it makes a difference. I have seen more than one case where the sense wire was connected to the tail light wire, and it was overcharging because the connectors that fed the tail light and, therefore, the sense wire, were dirty, not letting the sense wire 'see' enough voltage. When the connectors were cleaned, the output voltage came right down to where it should be.

.

Thanks Steve, I will do as has been suggested (move sense wire to battery) and test, I will also check I have the sense wire to the correct terminal on the brake light switch as you have suggested. The terminals definitely will not be dirty as complete harness and attachments have been overhauled. But I will check the other things mentioned for the "human error" factor. Which gets more "human" the "older" I get.

Thanks again.

[Suzuki_Don]

Warning... if your battery negative and the R/R grounds are not at the same voltage potential, she's going to regulate higher also. that method only works if the grounds are proper. (I use a jumper cable on the negative's to prove out that side when I'm too lazy)

How do I test for that? Talk SLOW so I can take it in and understand the process properly.

[tas850g]

I didn't read this in any posts but check the volt meter that is connected on your bike for accuracy. My voltmeter that is connected to my 850 is reading low by about a volt at 3-4k rpms. But when I check the vdc with a hand held meter at the battery it is within normal ranges (14.2 vdc at 3k rpms).

It probably is the sense wire low output at the rear brake that is causing the higher charging vdc but maybe worth checking the bike's voltmeter.

I had the same problem with my initial sense wire connection to the brake light. It was reading a low output thus high voltmeter readings. Lucabond installed a relay and connected the sense wire to it and fixed the problem.

[rustybronco]

How do I test for that? Talk SLOW so I can take it in and understand the process properly.

O k a y. . .

What I said was, the R/R's negative wire must be at the same voltage (potential) as the batteries negative. (both at zero volts for this discussion)

to make sure both the R/R and battery negatives are at the same voltage, temporarily, I hook a jumper from the R/R's negative wire (could also be the 'casing' or housing if internally connected) to the batteries negative post.

did this explanation clear it up for you?

Don,

What is the voltage difference between the R/R sense point (at the brake light) and the battery voltage at (+)? I'm guessing the brake light is lower by about 0.4V

And now you should know the reason Jim asked what He did!

also, the same applies to the negative side!

[Suzuki_Don]

to make sure both the R/R and battery negatives are at the same voltage, temporarily, I hook a jumper from the R/R's negative wire (could also be the 'casing' or housing if internally connected) to the batteries negative post.

did this explanation clear it up for you?

So just to double check; I run a jumper from the fins of the R/R to the "-ive" terminal of the battery and see if the charging rate alters on my voltmeter. Is that correct. Have I got it!!!!!!!!!!!!