Weird volt reading during choke use


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Stew
Posts: 323
Joined: Mon Oct 23, 2017 10:40 am
Location: Smokey Point, WA - USA
Motorcycle: 2000 GL1500 SE
2005 Honda CRF230F

Previous bikes:
2003 Honda Ruckus
1993 Honda Elite SR
1986 Honda CR125R
1979 Yamaha GT80

Weird volt reading during choke use

Post by Stew » Sat Mar 03, 2018 11:54 pm



I've got another question, is this normal: I've noticed during a cold start with choke on full that the alternator does not seem to be charging, volts stay around 11.5 which is clearly running off the battery. After 45 seconds or a minute when I bring the choke to half, the volts then go to normal.

I've only had this bike since October, haven't ridden a whole lot because of bad weather so I don't have a long history with it. When I first noticed it I thought "whew, good thing I installed the voltmeter, now I won't get stranded." But then as I took it off choke it started charging normally. Do any of you guys with voltmeters see this happening, or do you always have charging voltage with full choke?

I think it does it pretty consistently, it's long enough between riding that I sometimes forget to look, so it may not be every single time, but often enough.


Winging it every chance I get 8-)

19,119 miles when I got it from dad Oct 15, 2017 --- 24,253 miles and counting as of Sep 20, 2018!

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Erdeniz Umman
Posts: 693
Joined: Tue Oct 27, 2015 12:33 am
Location: Ankara Turkey
Motorcycle: 2000 GL1500SE

Re: Weird volt reading during choke use

Post by Erdeniz Umman » Sun Mar 04, 2018 1:27 am

The OEM alternators are weak to produce voltage at idle speed. You could replace it with a high output alternator like this one.

https://www.amazon.com/dp/B008EBCFSC/?tag=goldwingdocs-20 ... ingdocs-20

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MikeB
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Location: Tacoma, WA
Motorcycle: 1998 - GL1500 Aspencade.
2003 - GL1800A

Re: Weird volt reading during choke use

Post by MikeB » Sun Mar 04, 2018 2:22 am

Stew,

The voltmeter may be the issue. The next time you have it doing something weird like this voltage wise, take a known good Volt-Ohm-Meter (VOM) and put the probes on the negative and positive terminal of the battery and check the voltage there. If it is still going wonky on you, I'm at a loss as to what it is but I have a feeling you will find that the voltage is okay.
MikeB
Tacoma, WA, USA

User avatar
Stew
Posts: 323
Joined: Mon Oct 23, 2017 10:40 am
Location: Smokey Point, WA - USA
Motorcycle: 2000 GL1500 SE
2005 Honda CRF230F

Previous bikes:
2003 Honda Ruckus
1993 Honda Elite SR
1986 Honda CR125R
1979 Yamaha GT80

Re: Weird volt reading during choke use

Post by Stew » Sun Mar 04, 2018 2:09 pm

Erdeniz: Good thought but it shows the low voltage even when it's at 2000+ rpm.

MikeB: Well you were right, I didn't think to confirm with a separate VOM. The in-dash voltmeter reading has a mind of it's own at times apparently, it does in fact start charging immediately as verified by my trusty (other) voltmeter. See what I'm talking about in the video below.



Winging it every chance I get 8-)

19,119 miles when I got it from dad Oct 15, 2017 --- 24,253 miles and counting as of Sep 20, 2018!

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Erdeniz Umman
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Joined: Tue Oct 27, 2015 12:33 am
Location: Ankara Turkey
Motorcycle: 2000 GL1500SE

Re: Weird volt reading during choke use

Post by Erdeniz Umman » Sun Mar 04, 2018 2:28 pm

Interesting. If the voltmeter is good, there may be some issues at its connections. Any loose or corroded contact/connection will create resistance which will cause voltage drop on that circuit.

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MikeB
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Joined: Fri Dec 04, 2009 12:54 pm
Location: Tacoma, WA
Motorcycle: 1998 - GL1500 Aspencade.
2003 - GL1800A

Re: Weird volt reading during choke use

Post by MikeB » Sun Mar 04, 2018 3:19 pm

Nice voltmeter installation, Stew. Hopefully the voltmeter is working properly and you will not have to tear the dash apart to troubleshoot the issue.

Where is the source voltage coming from for the meter? If it is the accessory terminals, you probably should change it to the battery through a small fuse.

If it is through a relay that is energized by the accessory terminals, it could be the relay that is the issue. Wherever it is coming from, you will need to trace back from the meter to the source to inspect all the connections.

Years ago I had a similar meter installed and powered through a tubular fuse in a nylon fuse holder. The contact points of the fuse in the fuse holder got oxidized and caused some really flaky indications. I thought it was the alternator. Investigation identified the fuse holder. I changed the source wiring. I connected the meter to the battery through an auxiliary fuse panel. At the time of the original installation, I did not have the aux fuse panel and that was the reason for the tubular fuse and holder.
MikeB
Tacoma, WA, USA

User avatar
Stew
Posts: 323
Joined: Mon Oct 23, 2017 10:40 am
Location: Smokey Point, WA - USA
Motorcycle: 2000 GL1500 SE
2005 Honda CRF230F

Previous bikes:
2003 Honda Ruckus
1993 Honda Elite SR
1986 Honda CR125R
1979 Yamaha GT80

Re: Weird volt reading during choke use

Post by Stew » Sun Mar 04, 2018 3:49 pm

The voltmeter is wired to the battery through a standard 30/40 amp automotive relay, and the relay is switched by the accessory terminals. So other than being switched by the relay, the voltmeter has a direct path to the battery.

It would be easy enough to swap in another relay, I got a 5 pack when I got them a couple months ago and I also got the sockets that go with them so it's as easy as plugging a new one. It could be that the voltmeter is just poor quality, it's from Hong Kong or somewhere in Asia from ebay, the one from the DIY article I did.

Thanks for taking a look guys, I'm learning more and liking this motorcycle more every time I ride it :)
Winging it every chance I get 8-)

19,119 miles when I got it from dad Oct 15, 2017 --- 24,253 miles and counting as of Sep 20, 2018!

User avatar
MikeB
Posts: 2194
Joined: Fri Dec 04, 2009 12:54 pm
Location: Tacoma, WA
Motorcycle: 1998 - GL1500 Aspencade.
2003 - GL1800A

Re: Weird volt reading during choke use

Post by MikeB » Sun Mar 04, 2018 3:55 pm

If possible, as a test, connect the meter directly to the battery and run the bike again to see if the malfunction still occurs.


MikeB
Tacoma, WA, USA

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