I have a relatively new battery and make mostly 10 mile trips.  I went out yesterday and there was not enough juice to spark the motor.  It turned over for a while then died out, lamps were going dim.

I do have dual headlights.

I am wondering if there is an upgrade to make sure there is enough voltage getting back to the battery.

From what I've gathered here, you have to run the revs up a bit to get good voltage.

I tested the bike out and found that below 2000 rpm the load from the headlights and everything let the battery voltage fall. 
While riding to work I like to keep the revs low to conserve gas and the engine, but it appears I need to be up around 5000 rpm.

Is there an upgrade to the generator or something to improve this?

Turn off lights in day time, or run on 1 when you're like 3-4 miles form home or work, or somehting like that, LED tail lights and T/Ses may aldo help. Cant really upgrade the alternator, like  putting extra windings in it ... nope. Some dirt bikes had that option ... ours does not.
Cool.
Buddha.

The charging system doesn't kick in until 3500 rpm,until then you are running on pure battery powa.The charging system is checked with the bike at 5000 rpm where the charging system maxes out.

Try this. http://gstwins.com/gsboard/index.php?topic=38480.0

I work about 5 mins from home and ride all week short little jaunts then I park it. I also have dual headlights and have no problems with charging at all... Perhaps you should check your charging system.

Quote from: scottpA_GS on June 14, 2008, 06:42:20 PM

I work about 5 mins from home and ride all week short little jaunts then I park it. I also have dual headlights and have no problems with charging at all... Perhaps you should check your charging system.

Do you use a battery tender? I was going to suggest one for birdman, but your description suggests the GS charging system should be able to keep up with persistent short rides. I didn't think 5 minute rides would be enough to replace the energy required to start the bike 

Quote from: beRto on June 14, 2008, 08:35:17 PM

Quote from: scottpA_GS on June 14, 2008, 06:42:20 PM

I work about 5 mins from home and ride all week short little jaunts then I park it. I also have dual headlights and have no problems with charging at all... Perhaps you should check your charging system.

Do you use a battery tender? I was going to suggest one for birdman, but your description suggests the GS charging system should be able to keep up with persistent short rides. I didn't think 5 minute rides would be enough to replace the energy required to start the bike 

If you keep the rpm up.

Thanks for the replies.
yes I have a battery tender, IE charger, low amp.  Not my idea of convenient.

I suppose I need to check the output of the generator.
I wonder if its just not like everything else automotive.
Good parts / marginal performance.

With all our technology we should have no qualms with keeping the battery charged without thinking.

How do other bikes do it

Quote from: birdman on June 14, 2008, 05:37:35 PM


I do have dual headlights.

Does this mean you are running with x2 55/60w headlmap bulbs in the system instead of 1?

Yes, there are two bulbs on all the time. I think hi-beams probably suck serious juice.

Quote from: birdman on June 15, 2008, 07:08:49 AM
Yes, there are two bulbs on all the time. I think hi-beams probably suck serious juice.

I think this is where Sledge is going next...

http://gstwins.com/gsboard/index.php?topic=41136.msg462786#msg462786

In your case, replace hand grips (24 W) with extra bulb (60 W), for a total draw of 244W.

You have answered your own question, the GS electrical system simply does not have the capacity to cope with an extra 55w being drawn off the system. The power that would normally be charging your battery is being used by the extra headlamp. Take one of the bulbs out and run the bike without if for a few weeks and see if there is an impovement. You might find someone like Electrosport offers an uprated stator but I doubt  it will be big enough to produce an extra 55w. If you want more power you need to increase physical size and thats a problem with the GS5.

Thanks for the link beRto.
I can see how this is a problem. The PO put the duals on so I didn't really concern myself.
I will rewire the headlights.  One will be the driving light and the other will be high beam only.

Too bad there isn't a decent LED headlight replacement.

Thanks for the input folks
birdman