alternator output

[comatose]

I'm looking to add a few accessories(speakers) including a heated jacket and gloves,
by chance does anyone know what the alternator output(watts) is for the 2009 Softail Deluxe ?

[Pete]

Originally Posted by comatose

I'm looking to add a few accessories(speakers) including a heated jacket and gloves,
by chance does anyone know what the alternator output(watts) is for the 2009 Softail Deluxe ?

I ride a 2008 XL883, so I don't have the alternator outlput for your bike. I can tell you that the FI bikes have considerably more electrical capacity than the earlier machines with carburetors.

A 2008 Sportster is a 32 amp bike. That information is not hard to come by, what is tougher to find is the electrical draw that the bike places on the system. Electronic fuel injection uses more current than a carburetor does, but I have yet to get anyone from Harley to tell me how much.

What I did was to install a volt meter on the bike and then add in accessories and heated gear to see how much load it could take. Fortunately, the Sportster has a lot more electrical capacity than I expected. Wearing heated pants liners, jacket liner, and heated gloves, with their thermostats wide open, the bike easily handles the load while it is moving. At lower rpm's, such as at a stop light, the system can't keep up.

This is not an issue unless you were to spend a lot of time just idling. The solution is to turn the thermostats down when idling for protracted times or to increase the idle speed with the throttle. The volt meter does a great job of letting you know the state of your charging system in real time.

I just added two 55w auxiliary lights this summer. Again, the system handles them with ease as long as the engine is not at an idle. So far, I have not tested the new auxiliary lights with the heated liners. I suspect that the additional 110w load and the heated gear on maximum [I only rarely have ever had to turn the thermostat up beyond 50%.] might be too much for the system, but I won't know until I give it a try.

My options then are to install 35w instead of 55w bulbs in the auxiliary lights or just not run them when the heated gear is creating a big load on the system. Since I don't ride at night very much in the winter and thus don't need the auxiliary lights, this probably won't be much of a real-world issue.

To answer your question, if my Sportster can handle the load, then I suspect that your Softail can too.

Pete

[comatose]

Thanks Pete, someone just emailed me and said this is what my bikes specs are:
Three phase 38-amp system (439W @ 13V, 2000 rpm, 489W max power @ 13V)

now i'm curious how many watts are left when a stock bike is running normal,
or in other words, how much of that 439W are left after a stock bike goes thru all it's draws, you know, lights,fuel injector, etc etc.

[SCHMIDTYS]

Originally Posted by comatose

Thanks Pete, someone just emailed me and said this is what my bikes specs are:
Three phase 38-amp system (439W @ 13V, 2000 rpm, 489W max power @ 13V)

now i'm curious how many watts are left when a stock bike is running normal,
or in other words, how much of that 439W are left after a stock bike goes thru all it's draws, you know, lights,fuel injector, etc etc.

In this case the total output of your alternater would be irrelevent ... you'll be connected to a specific fused circuit , usually 15a , not the 40a maxi fuse . Use the PIE formula to figure out the watts capacity then tally the total watts of the things you plan to add to see if they'll work on a single 15a circuit . Also attatch any added grounds to the dirty ground lug ( black wire ) not the clean ground ( black / green wire ) . If you plan on using the acc. main B+ connector for power then do an inline fuse .

[Pete]

Originally Posted by SCHMIDTYS

In this case the total output of your alternater would be irrelevent ... you'll be connected to a specific fused circuit , usually 15a , not the 40a maxi fuse . Use the PIE formula to figure out the watts capacity then tally the total watts of the things you plan to add to see if they'll work on a single 15a circuit . Also attatch any added grounds to the dirty ground lug ( black wire ) not the clean ground ( black / green wire ) . If you plan on using the acc. main B+ connector for power then do an inline fuse .

The output of the electrical system is a know value; what is unknown is how much the bike draws for the EFI and other functions. In other words, how much electrical capacity is left in reserve after the basic bike functions have been powered. That information has not been easy to obtain from Harley Davidson.

It is pretty easy to calculate the draw of a light bulb or electrically heated clothing. It's not so simple to figure out the load imposed on the system by an electronic fuel injection system.

Knowing the rating of a fuse is important in keeping you from overloading that particular branch circuit, but it does little to tell you how much excess capacity your bike has to run accessories. A lot of motorcycles don't have enough electrical capacity to run heated liners or other heated clothing.

A fellow that I know bought a light bar for his older Sportster only to find that the bike could not generate enough current to keep it from discharging his battery. The Gerbing heated gear that he bought on sale that summer will have to wait until he buys a bike with a bigger electrical reserve.

Pete

[Pete]

Originally Posted by comatose

Thanks Pete, someone just emailed me and said this is what my bikes specs are:
Three phase 38-amp system (439W @ 13V, 2000 rpm, 489W max power @ 13V)

now i'm curious how many watts are left when a stock bike is running normal,
or in other words, how much of that 439W are left after a stock bike goes thru all it's draws, you know, lights,fuel injector, etc etc.

I would have expected a Softail to have more than a 38-amp system! That is only 6-amps more than a Sportster on a bike that gets a lot of two-up riding time. If you put two people on that machine with heated gear, it would be iffy as to how well it could handle the load.

Considering the size of a Softail engine, I would have expected it to have at least a 50-amp system.

Pete

[SCHMIDTYS]

Originally Posted by Pete

I would have expected a Softail to have more than a 38-amp system! That is only 6-amps more than a Sportster on a bike that gets a lot of two-up riding time. If you put two people on that machine with heated gear, it would be iffy as to how well it could handle the load.

Considering the size of a Softail engine, I would have expected it to have at least a 50-amp system.

Pete

The ecm circuit uses a 2a fuse so using the pie formula 2a x 13v = 26w max .
Again using the pie formula 38a x 13v = 494w .
Most newer charging systems I test put out over 14v under load . At 14v the 38a output would yield 532w .
These are all formula numbers . Normally in a 15a circuit I see less than half of that number when I test the current in series at the fuse .

[comatose]

the bike comes with a battery overcharging/undercharging warning light, wouldn't that light up if i'm using to many accessories with to much draw ?
or am i mistaken about that warning light ?

[SCHMIDTYS]

The only warning light that I'm aware of is the flash / spark given off when the fuse blows ! The old Harleys had a gen. light that would illuminate when the output was low but newer Harleys don't have a light like that . You'll know when your charging system isn't working when your battery goes dead .

[Dave63]

The 2009 has a charging system light as do most big twins back to 2006 with EFI.

Yes....If the bike is using more electricity then the regulator is "asking" for, or the stator is capable of producing, then the light will trigger. I believe the light is controlled via the ECU, but I could be wrong.

If this is allowed to continue, the bike will get the needed power from the battery, until that's dead, and the bike will shut down.