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Offline magscm400t

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not always bright
« on: June 29, 2017, 07:41:46 AM »
New to site, any help would be great
I have a 1980 CM400T and the lights and blinker are sometimes dim at an idle, but not always.  I have a new battery. I am thinking voltage reg.
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Offline flybox1

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Re: not always bright
« Reply #1 on: June 29, 2017, 09:45:22 AM »
what is the voltage (taken at the terminals) of said new battery?
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Offline MoMo

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Re: not always bright
« Reply #2 on: June 29, 2017, 09:45:37 AM »
Quote from: magscm400t on June 29, 2017, 07:41:46 AM
New to site, any help would be great
I have a 1980 CM400T and the lights and blinker are sometimes dim at an idle, but not always.  I have a new battery. I am thinking voltage reg.


First, check the charging with a voltmeter  and make sure it is 14.7v or thereabouts at 3000 rpm.  Seems to me that you need to go through and clean all connections, especially grounds, which are green wires.  Pay particular attention to battery cables.  Welcome...Larry
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Offline magscm400t

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Re: not always bright
« Reply #3 on: June 29, 2017, 10:17:48 AM »
The voltage shows to be 12.7 at the battery.  I did notice the most of the time I turn on the ignition switch and all of the lights come on and all works, on occasion nothing lights up or works (I.E starter).  I will clean grounds tonight.
thanks!
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Offline MoMo

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Re: not always bright
« Reply #4 on: June 29, 2017, 02:27:24 PM »
Quote from: magscm400t on June 29, 2017, 10:17:48 AM
The voltage shows to be 12.7 at the battery.  I did notice the most of the time I turn on the ignition switch and all of the lights come on and all works, on occasion nothing lights up or works (I.E starter).  I will clean grounds tonight.
thanks!


Are you saying voltage does not rise over 12.7 when engine is revved???
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