New battery discharges when the lights are on

[IanFrancisco]

Hello everyone: A couple of months ago I was inquiring about the usual charging system woes we experience with our GS's. So as a result of that, I ended up printing out the Stator Papers from this site (great info) and using them to determine that the stator in my GS450S was good (no shorts and 60+ volts AC at 4500rpm) and my reg/rec (RR) was not good. Bought the Electrex RR and installed it and went thru my entire harness cleaning and reseating all the connectors incl. the battery cables and all grounds. Bought a new Yuasa battery for my bike, filled it w/ acid/electrolyte and charged it with my new DieHard 1.5 amp smart charger. Only took about 8 hrs. to charge up completely, lighting the green "good to go" led on the charger. Thought my problems were solved but I still can't cruise around at 3000-5000 rpm with the lights on. After an hour and a half ride around town (stop n go) the battery has discharged to the point where the starter won't crank. I can still bump start it in 2nd gear w/ no problem. The battery charges right back up in 2 or 3 hrs. on the charger. I'm running an H4 halogen headlight. Does this light just suck up too much juice for the stock stator to keep up with? I don't have a problem with the battery discharging when 1) I leave the lights off or 2) I run at high revs (6000 or more), even around town. I would rather not have to do either 1) or 2). Is this something I'm just going to have to live with?

Thanks guys.

[Anonymous]

I have not had an issue with the H4 bulb and discharging my battery, except when I had a short in my fuel gauge wire....you may want to check your wiring over and make sure you do not have a burnt or fried wire somewhere that is causing an issue with your battery charging.

PS-A friend of mine just had a similar issue with a yamaha and found a fried wire last week. He cut it/crumped it and hasn't had a problem since.

[Anonymous]

Probably a connector problem, I had electrical problems, cleaned all connectors, didn't help, ended up replacing them and soldering the crimps - problem solved. Turned out to be that you get a high resistance on the (aged) crimps due to corrosion on the wire, no problems with normal low amp circuits but on the high amp ones (lighting/starter) it is.

[IanFrancisco]

connectors

My GS450S is amazingly well preserved, had 8000 miles put on between 1980 and 85 then was stored in the garage most of the time after that until I got it 3 months ago. The wires all look new, the previous owner started it periodically and even Armor-alled the tires to try and prevent dry-rot (didn't work - new tires were the first thing I did). But - your suggestion sounds reasonable, so I'll go thru the harness again, paying very close attention to the lighting and charging circuits. The lights all work and are plenty bright, my problem seems to be that the charging circuit is weak and can't push enough current into the battery even though the stator puts out 60+ volts at 4500 rpm and the RR is a new Electrex. I may try running a separate ground wire directly from the RR to the battery and see if that helps.

Thanks for a good suggestion!