Voltage Reading

[Canadian FJR]

What is the lowest reading one can run at and for what length of time before the charging system could be damaged. I just added some PIAA lights and usually run an electric vest. The voltmeter shows around 13.0

If needed I can start switching but I am curious on what is considered safe. Total new lights are 55watts (each) and the vest is 34 watts. I realize that I only have 110 - 120 watts to run accessories.

Canadian FJR

 

[PerfectBlueride]

Since many times I walk out to get on my bike and my volt meter is displaying around 12.89, It would make me think that you should be fine.

I am sure the experts will be along and advise the facts hope this helped. :yahoo:

 

[Ignacio]

There probably isn't a specific black and white voltage number that things will be all well if above and go to crap if below. It's probably not even a linear scale. There's probably some logarithmic scale out there on stator life at various loads. I think technically, anything over 12.6 is resulting in a net charge to the system.....but again that's the technical limit.

Rule of thumb I go by is under 13 volts for extended periods and it's probably going to prematurely wear the stator out. It will heat up and eventually short out. I've seen pictures of Warchild's fried Blackbird or ST1100 stator.

13 to 13.5 is giving it a workout.

Over 13.5 and it's probably OK for extended periods.

Results will vary. You gotta ask yourself the question if you're going to run all that gear.

What happens if I lose charging all of a sudden in the middle of the night 50 miles from the nearest town? If you turn off your gear and disconnect every light except one will you have enough juice to make it to civilization?

 

[radman]

What happens if I lose charging all of a sudden in the middle of the night 50 miles from the nearest town? If you turn off your gear and disconnect every light except one will you have enough juice to make it to civilization?

Not likely. Tough to disconnect them all-unless you start yanking fuses, and we all know how much fun that can be. Time was, a bike needed very little to continue in emergency mode-I've done 50 miles with no charging system-but that bike didn't have a volt sensitive ECM and injection to run, which would be the limiting factor. Plus, if this were a situation where the system failed because of too many goodies cooking the stator, likely the battery isn't in all that great a condition to begin with. Not a good scene.

 

[charismaticmegafauna]

Canadian FJR: All replies are on the mark; but, Iggy is closest. The issue is W=VxA. If you put your math skills at work here, you'll see as volts go up amps go down. It's the amps (current flow) that overheats and fries the stator. So, like Ignacio advised, the higher the volts -- the less the risk. Btw, the FJR puts out max power all the time (once the revs are up to a certain speed) -- so, with no way to control the alternator output -- it becomes imperative to keep the voltage high (for stator life).

As they wisely counsel, "Husband your electricity..."

 

[Rickster]

What is the min RPM is needed to get over the battery 12 v?

(I had a learning experience with my Aprilia, would not charge unless you were > 5K RPM)

 

[SkooterG]

What is the min RPM is needed to get over the battery 12 v?
(I had a learning experience with my Aprilia, would not charge unless you were > 5K RPM)

Under a *normal* electrical load, alternator is putting out around 14.5 volts at idle speed according to my voltmeter.

*However*, it's not putting out maximum power or watts, which is a whole different beast, until 5000rpm I think it is, according to Yammie's specs.

 

[Rickster]

Thanks skooter! i guess 5 grand may be the standard! same on my aprilia, not the JFR!