Electrical load 50r

[Optimus Prime]

Thanks to Aerostich and Gerbings, I've been able to cure my PMS (Parked Motorcycle Syndrome) and ride down into the 20's. I have a small LED Voltmeter that runs green when the Volts are between 12-15, Amber between 11-12, Red between 10-11, blinking red below 10, blinking green above 15. It's wired into a random 12V source in the gage cluster since the wires weren't long enough to get to the battery, so the source may be questionable.

Anyways, on to the question:
I have recently seen the "amber" color appear. Only when stopped and idling with the following on:
*Gerbings Jacket Liner
*Hand grips on high (They aren't working for shit anymore, FYI)
*PIAA driving lights (55W=110W)
*Brakes (ie. Servos :021: )

All it takes is a blip of the throttle or getting rid of one of the above loads and I'm back in the green. Is this acceptable?

[Dallara]

Perfectly acceptable, Optimus...

That is, of course, unless you plan to spend all your time idling somewhere instead of riding... :037:

Here's some info on what the R1150R's alternator puts out...

Stock Alternator Output Specs
_____________________________
Output:
Total Watts Output
RPM...................Watts
Max....................700
4000...................700
2500...................475
1,000..................252

And here's some info on how much juice some of the systems draw on the R1150R...

Draw:
Engine....................?
ABS........................?
Headlight/High.........60
HeadlightLow...........55
Taillight....................5
Brake Light...............21
License....................6
Turnsignals..............21 (Each)
Instrument Lights.....1.7 (Each)
Starter..................1,100

You depend on the battery's storage capacity to handle the huge draw of the starter, and then the alternator pumps the battery back up. In fact, after the bike is started the entire bike runs off the battery, while the alternator more than keeps up with the load and depletion of charge.

Add up the wattages of your extra electrical items and start subtracting them from the idle output above and you will see it is pretty easy to put the battery into *deficit spending*... However once you come off idle you are apparently going back to putting charge *back in the bank*.

If your light is only going amber at idle I wouldn't worry about a thing.

Hope this helps!

Allan (Dallara - NACD)

[Optimus Prime]

Perfectly acceptable, Optimus...

That is, of course, unless you plan to spend all your time idling somewhere instead of riding... :037:

Here's some info on what the R1150R's alternator puts out...

Stock Alternator Output Specs
_____________________________
Output:
Total Watts Output
RPM...................Watts
Max....................700
4000...................700
2500...................475
1,000..................252

And here's some info on how much juice some of the systems draw on the R1150R...

Draw:
Engine....................?
ABS........................?
Headlight/High.........60
HeadlightLow...........55
Taillight....................5
Brake Light...............21
License....................6
Turnsignals..............21 (Each)
Instrument Lights.....1.7 (Each)
Starter..................1,100

You depend on the battery's storage capacity to handle the huge draw of the starter, and then the alternator pumps the battery back up. In fact, after the bike is started the entire bike runs off the battery, while the alternator more than keeps up with the load and depletion of charge.

Add up the wattages of your extra electrical items and start subtracting them from the idle output above and you will see it is pretty easy to put the battery into *deficit spending*... However once you come off idle you are apparently going back to putting charge *back in the bank*.

If your light is only going amber at idle I wouldn't worry about a thing.

Hope this helps!

Allan (Dallara - NACD)

Thanks :thumbs_up:

I wasn't sure how much the Alternator was putting out at low RPM's and I wanted to make sure I was putting enough back into the battery at freeway speeds.

Without ABS or Engine numbers it looks like I'm around 300 W's when stopped.

[socalrob]

Sorry to bring this thread back to life, must have missed it first time around.

Dallara, if the starter draws 1,100 watts, and the alternator puts out 475 watts at 2,500 rpms, and it takes say at most 10 seconds cranking to start the bike, wouldn't the battery be fully recharged within at most a minute of riding / idling at 2,500 rpms?

Reason I ask is it seems most everyone believes anything under 15 or 20 minutes of riding will not charge the battery. I've always felt that was not true, as my old commute was only about 4 minutes, & the battery never seemed to drain down even after many short rides. Plus, doesn't seem practical to make a transportation device that requires more than 10 minute trips to recharge the battery. What are your thoughts?

[Sir Limpsalot]

The 15 to 20 mins that people quote to replace in the battery what the starter took out harks back to the "bad old days" of dynamo and controll box systems.
Modern alternators do waaaaaay better.
At work when I am testing battery and/or alternator performance our company insist we run the engine for five mins at fast idle (with all loads off) before commencing the test. This is proven to be more than enough time for the battery to recover if it's going to and is deemed sufficient to allay any fears of underhand behaviour (ie selling a battery that is not required etc).
Worry not, just ride it like you always have!
Si

[jamais]

Simon, you're bio says you're a mole hunter. Is that in four legged creatures or as in MI6?

[Sir Limpsalot]

the "mole" thing was a joke (not very funny I grant you!) when we were starting up this thing. Some bugger was reporting our movements back to an old site we used to frequent. This individual became known as the "mole" (as in spy or MI6) and gave rise to several feeble jokes like mine.
I shall have to go back to my bio and change it. I work for the AA (that's the Automobile Association not the booze lot.........) and repair vehicles at the roadside. In the pissing rain. At midnight. On Christmas day. On New Years Eve. In fact I do it when every other right minded family man is home with his wife and kids, or off riding his motorcycle, or down the Pub having the odd glass of Ale. The pay's not wonderfull either...........
Err, sorry Jamais, what was the question??????????????
Si