Alternator output on the 08.

Spridal · Apr 3, 2008

Before you roast me please note that I did use the search function and google

... here's my question, does anyone know the #of amps that the 08 alternator puts out?

Ignacio · Apr 3, 2008

It's a math question.

Watts = Volts x Amps. So we know from the Bin O' Facts that Watts for a Gen II is 590 watts. We know the produced voltage without a major load is about 14 volts. So amps are 590/14 = 42.

Spridal said:
Before you roast me please note that I did use the search function and google...

Now, do your part and send a PM to Rickster to get this data updated in the Gen II FAQ.

Rickster · Apr 3, 2008

The Gen II Bin has been updated

Wicked Webby · Apr 3, 2008

Rickster,

Wow!!! You on the ball. Good job!!!!!

WW

Rickster · Apr 4, 2008

Wicked Webby said:
Rickster,
Wow!!! You on the ball. Good job!!!!!

WW

thanks. I try!

Spridal · Apr 4, 2008

Thanks all! So if the 08 puts out 42 amps and my farkles consume about 13 amps, looks like I can safely run them without worry.

ionbeam · Apr 4, 2008

Just to be picky --> from 5,000 rpm and up you have 42 amps available (590 watts), there are a lot less amps available below 5,000 rpm. Your farkles want to consume as much as 13 amps (180 watts). I seriously suggest that you include a volt meter that reads battery voltage. If you actually use all 13 amps, then from idle to ~2,500 rpm you may be over taxing your stator and not charging your battery or possibly even depleting it. This won't kill the stator outright, but it will hasten its demise. I've seen some pretty neat pictures of crispy stator wires from our FJRs.

Glad you were able to access your signal relay without a bunch of work!

Spridal · Apr 4, 2008

ionbeam said:
Just to be picky --> from 5,000 rpm and up you have 42 amps available (590 watts), there are a lot less amps available below 5,000 rpm. Your farkles want to consume as much as 13 amps (180 watts). I seriously suggest that you include a volt meter that reads battery voltage. If you actually use all 13 amps, then from idle to ~2,500 rpm you may be over taxing your stator and not charging your battery or possibly even depleting it. This won't kill the stator outright, but it will hasten its demise. I've seen some pretty neat pictures of crispy stator wires from our FJRs.
Glad you were able to access your signal relay without a bunch of work!

Thanks for the input. I have the charge guard installed and it appears with all my farkles on it draws about 9 amps. I will double check the volt readings when I get back home on sunday and will report back.

Spridal · Apr 4, 2008

Spridal said:
ionbeam said:

Just to be picky --> from 5,000 rpm and up you have 42 amps available (590 watts), there are a lot less amps available below 5,000 rpm. Your farkles want to consume as much as 13 amps (180 watts). I seriously suggest that you include a volt meter that reads battery voltage. If you actually use all 13 amps, then from idle to ~2,500 rpm you may be over taxing your stator and not charging your battery or possibly even depleting it. This won't kill the stator outright, but it will hasten its demise. I've seen some pretty neat pictures of crispy stator wires from our FJRs.
Glad you were able to access your signal relay without a bunch of work!

Click to expand...

Thanks for the input. I have the charge guard installed and it appears with all my farkles on it draws about 9 amps. I will double check the volt readings when I get back home on sunday and will report back.

By the way, what would be the target # for volts that I should make sure I try to maintain?

HaulinAshe · Apr 4, 2008

Spridal said:
By the way, what would be the target # for volts that I should make sure I try to maintain?

Most sealed batteries like the FJR uses have idle voltages around 12.8 volts. Best answer I can give you is check the idle voltage with whatever meter you intend to use and an extremely light load (such as the digital meter itself and nothing more). That voltage reading is the minimum battery voltage. Anything below that means you are sucking more amps than the stator can blow, and the battery is constantly being discharged.

This way you are taking into consideration variations in meter calibration, individual battery characteristics, voltage drop across wiring etc.

ionbeam · Apr 4, 2008

Excerpted from a previous thread

With a good charging system, and a healthy, properly charged battery I would offer these guidelines for sustained voltages:

≤12.8 volts at the battery terminals – the charging system is over taxed, the battery is being discharged, and the stator is in danger of being permanently damaged.

12.8 to 13.2 volts – entering the danger zone, the battery is no longer being trickle charged and the stator is being taxed to the limits.

13.2 – 13.7 volts – sustainable, the stator is taxed but the battery is being charged.

13.7 to 14.5 volts – schweet

Spridal · Apr 4, 2008

ionbeam said:
Excerpted from a previous thread
With a good charging system, and a healthy, properly charged battery I would offer these guidelines for sustained voltages:

≤12.8 volts at the battery terminals – the charging system is over taxed, the battery is being discharged, and the stator is in danger of being permanently damaged.

12.8 to 13.2 volts – entering the danger zone, the battery is no longer being trickle charged and the stator is being taxed to the limits.

13.2 – 13.7 volts – sustainable, the stator is taxed but the battery is being charged.

13.7 to 14.5 volts – schweet

Thanks for the very, very helpful information.

TriggerT · Apr 19, 2008

Yes, thanks for the info on what the volt meter should read. I am getting ready to put a Datel on my bike, and it is great to know what it should be reading. :yahoo:

dcarver · Nov 5, 2008

oops

LAF · Feb 8, 2012

So in resurrecting this old thread I just installed a Datel on my 10. I am seeing no reading over 13.80 with almost everything off. I was running 13.26 and turned my Moto Lights off and that is when I read 13.80 as a max reading.

Now the stupid question. I have it installed with a 5 amp inline fuse from positive lead off battery to the Datel positive lead. Am I creating any kind of resistance or impedance that will show up in the Datel readings?

If not what would be the reasons I am only seeing 13.80 as a max with very little draw? TPI monitor, AddMore light kit in the Givi, Power Commander,, 660 Garmin, and of course the headlights (on low) are the only things on.

Electric is not my thing and any help insights would be appreciated.

I know I am not seeing the numbers posted in Ionbeam's above post and never saw over 13.80.

Should I put a tender on my battery and check it with a meter on the battery to see if it matches the Datel?

Thanks for any help.

ionbeam · Feb 8, 2012

LAF said:
So in resurrecting this old thread I just installed a Datel on my 10. I am seeing no reading over 13.80 with almost everything off. I was running 13.26 and turned my Moto Lights off and that is when I read 13.80 as a max reading...

You need to use a DMM and measure directly across the posts of the battery, not the terminal screws but the battery terminals themselves. If you measure the terminal screws the reading would include any terminal to screw (loose screws?) resistance and resulting voltage drop. If the battery terminal reading is 14.x volts then you are looking at the terminal connections or wiring resistance. More details depending on what you see. If all you see is <13.9 volts we are looking at a battery/charging issue.

Now the stupid question. I have it installed with a 5 amp inline fuse from positive lead off battery to the Datel positive lead. Am I creating any kind of resistance or impedance that will show up in the Datel readings?

The Datel draws so little current that the voltage drop across the fuse should be negligible. But, after troubleshooting another install we discovered a defective fuse socket causing a voltage drop.

If not what would be the reasons I am only seeing 13.80 as a max with very little draw? TPI monitor, AddMore light kit in the Givi, Power Commander,, 660 Garmin, and of course the headlights (on low) are the only things on.

I have seen voltage drops occur at the starter relay. The output of the R/R goes to the STARTER RELAY first, on 12 ga wires (IIRC), then from those studs goes the heavy gauge battery wires to the battery. I have seen voltage drops at the starter relay studs; a simple clean and reconnect has fixed the voltage drops from an otherwise normal running electrical system.

Should I put a tender on my battery and check it with a meter on the battery to see if it matches the Datel?

If the battery voltage is low at the terminals you should put the battery on a trickle charger. If you have to do this, there are some diagnostic steps that need to be done to determine if your problem is the charging system or the battery. After declaring any late model Gen II charging system as bullet proof a Forumite found a defective stator and replacing it fixed his low battery voltage.

Matt101 · Feb 8, 2012

This site is just full of brilliant info :clapping:

wheatonFJR · Feb 8, 2012

Matt101 said:
This site is just full of brilliant info :clapping:

...and usually the poster you see spouting off that info. is ionbeam.

That guy is just too danged smart and helpful!

LAF · Feb 8, 2012

All I know at this time is it is snowing!

Well also my Craftsman Volt Meter and the Datel don't read the same. Seems the Craftsman is optimistic by .06, or the Datel is off, either way not enough for me to fuss over yet. As it started to snow I just pulled the battery and took it downstairs and popped the Optima charger I just got new.

I am going to charge it to it says it is good and on maintain charge. Then I am going to take the charger off and let it sit and get a "at rest" voltage reading. I think snow is over tonight so in the late AM will hook it up in the bike with everything connected. Take a reading, turn key to on take reading, start bike and take reading. After I see how that plays out I think I will disconnect things see what happens, taking readings as I disconnect each thing. Then if I see no big thing I will ride it to see if the charging of the battery did any thing.

After that I will check the cables, ground and hot at the next termination point.

After that I will need help, or before if I should do something other then what I intend to do.

As I said I am lost on electrics and have no clue.

I am going to get the FM out and start looking at where these battery cables go to from the ends I see at the battery.

Alternator output on the 08.

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