I need hd forums touring section help !
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
well,
at idle the charging system ( alternator and regulator) is not "adding" voltage...
as a rule of thumb the alternator produces about 16~20 volts AC ( not DC) per 1000 rpms.
then the AC current gets rectified to DC ...which burns off some volts...by the regulator- the regulator also limits the output to below 14.8 volts DC.
these are all numbers using a "real" voltmeter...not the in dash, which is as useful as an idiot light.
so at idle, the bike is really running off the battery...and maybe you'll see a reading of 12 volts or a little more measured at the battery...and this will vary depending on high beam, flashers and any other loads on the electrical system.
HEAT build up in wiring builds resistance against current flow- this is why hot starts can be difficult on any bike or car- especially if the cables are loose or corroded.
and resistance in the wiring results in even more heat...which results in more resistance and even more heat... and the snake eats it's tail and the wiring can burn up ( this is why aluminium wiring in 70's houses was/is such a bad idea)
mike
at idle the charging system ( alternator and regulator) is not "adding" voltage...
as a rule of thumb the alternator produces about 16~20 volts AC ( not DC) per 1000 rpms.
then the AC current gets rectified to DC ...which burns off some volts...by the regulator- the regulator also limits the output to below 14.8 volts DC.
these are all numbers using a "real" voltmeter...not the in dash, which is as useful as an idiot light.
so at idle, the bike is really running off the battery...and maybe you'll see a reading of 12 volts or a little more measured at the battery...and this will vary depending on high beam, flashers and any other loads on the electrical system.
HEAT build up in wiring builds resistance against current flow- this is why hot starts can be difficult on any bike or car- especially if the cables are loose or corroded.
and resistance in the wiring results in even more heat...which results in more resistance and even more heat... and the snake eats it's tail and the wiring can burn up ( this is why aluminium wiring in 70's houses was/is such a bad idea)
mike
Last edited by mkguitar; Jul 26, 2013 at 12:15 PM.
well,
at idle the charging system ( alternator and regulator) is not "adding" voltage...
as a rule of thumb the alternator produces about 16~20 volts AC ( not DC) per 1000 rpms.
then the AC current gets rectified to DC ...which burns off some volts...by the regulator- the regulator also limits the output to below 14.8 volts DC.
these are all numbers using a "real" voltmeter...not the in dash, which is as useful as an idiot light.
so at idle, the bike is really running off the battery...and maybe you'll see a reading of 12 volts or a little more measured at the battery...and this will vary depending on high beam, flashers and any other loads on the electrical system.
HEAT build up in wiring builds resistance against current flow- this is why hot starts can be difficult on any bike or car- especially if the cables are loose or corroded.
and resistance in the wiring results in even more heat...which results in more resistance and even more heat... and the snake eats it's tail and the wiring can burn up ( this is why aluminium wiring in 70's houses was/is such a bad idea)
mike
at idle the charging system ( alternator and regulator) is not "adding" voltage...
as a rule of thumb the alternator produces about 16~20 volts AC ( not DC) per 1000 rpms.
then the AC current gets rectified to DC ...which burns off some volts...by the regulator- the regulator also limits the output to below 14.8 volts DC.
these are all numbers using a "real" voltmeter...not the in dash, which is as useful as an idiot light.
so at idle, the bike is really running off the battery...and maybe you'll see a reading of 12 volts or a little more measured at the battery...and this will vary depending on high beam, flashers and any other loads on the electrical system.
HEAT build up in wiring builds resistance against current flow- this is why hot starts can be difficult on any bike or car- especially if the cables are loose or corroded.
and resistance in the wiring results in even more heat...which results in more resistance and even more heat... and the snake eats it's tail and the wiring can burn up ( this is why aluminium wiring in 70's houses was/is such a bad idea)
mike
so what does your gauge read that's all i asked simple.?examples 12.5v 13.5v 14v with no accessories just what a stock motorcycle has on normally BTW i put a fluke meter on against the dash gauge and it was spot on
Road Captain
Joined: Jul 2010
Posts: 503
Likes: 1
From: Missouri
well,
at idle the charging system ( alternator and regulator) is not "adding" voltage...
as a rule of thumb the alternator produces about 16~20 volts AC ( not DC) per 1000 rpms.
then the AC current gets rectified to DC ...which burns off some volts...by the regulator- the regulator also limits the output to below 14.8 volts DC.
these are all numbers using a "real" voltmeter...not the in dash, which is as useful as an idiot light.
so at idle, the bike is really running off the battery...and maybe you'll see a reading of 12 volts or a little more measured at the battery...and this will vary depending on high beam, flashers and any other loads on the electrical system.
HEAT build up in wiring builds resistance against current flow- this is why hot starts can be difficult on any bike or car- especially if the cables are loose or corroded.
and resistance in the wiring results in even more heat...which results in more resistance and even more heat... and the snake eats it's tail and the wiring can burn up ( this is why aluminium wiring in 70's houses was/is such a bad idea)
mike
at idle the charging system ( alternator and regulator) is not "adding" voltage...
as a rule of thumb the alternator produces about 16~20 volts AC ( not DC) per 1000 rpms.
then the AC current gets rectified to DC ...which burns off some volts...by the regulator- the regulator also limits the output to below 14.8 volts DC.
these are all numbers using a "real" voltmeter...not the in dash, which is as useful as an idiot light.
so at idle, the bike is really running off the battery...and maybe you'll see a reading of 12 volts or a little more measured at the battery...and this will vary depending on high beam, flashers and any other loads on the electrical system.
HEAT build up in wiring builds resistance against current flow- this is why hot starts can be difficult on any bike or car- especially if the cables are loose or corroded.
and resistance in the wiring results in even more heat...which results in more resistance and even more heat... and the snake eats it's tail and the wiring can burn up ( this is why aluminium wiring in 70's houses was/is such a bad idea)
mike
Tourer
Joined: Jul 2011
Posts: 311
Likes: 1
From: Florida
Mike, good explanation. Jerseyjeff, Mike says about 12V. Remember he is reading from a volt meter. I don't think he trusts the volt gauge on the fairing. If you are asking what the volt gauge will read at idle, ur asking for an estimate reading as the gauge will read a little different from gauge to gauge. About 11.5 - 12.0 at idle. It would be best to hook up a volt meter and measure it against the reading on ur gauge. Then you will know for sure. Ask a neighbor over for a beer and say "U got a minute". Works every time. Especially on a bike.
Good Luck
FLHPRK
Good Luck
FLHPRK
Here's an answer for you. Mine drops down to 10 or 11 at idle when hot. Never had trouble with it. Rev engine - it goes right back up to 13-14V. If the battery has a lower than topped up charge, it will indicate a bit higher when at idle until the battery is happy.
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I am trying to tell a harley mechanic that there is something wrong with my charging system because mine goes to 12.5volts at idle and he told me that's within harley spec's.well then the last 4 harley's that i had,and my wifes and my brother's bikes must be overcharging they're always 14v's and last season my bike was 14v too
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
is this the kernal you were looking for?:
what ever you do, do NOT make decisions based on the in-dash voltmeter.
specs for the charging system are published in the shop manual...that'll settle an argument
if my 1st response was long winded- I am fueled by "fog breaker" coffee from Fresh and Easy markets...and I thought it may be helpful for an owner to have a basic understanding of charging system function.
Mike
what ever you do, do NOT make decisions based on the in-dash voltmeter.
specs for the charging system are published in the shop manual...that'll settle an argument
if my 1st response was long winded- I am fueled by "fog breaker" coffee from Fresh and Easy markets...and I thought it may be helpful for an owner to have a basic understanding of charging system function.
Mike
Last edited by mkguitar; Jul 26, 2013 at 03:17 PM.