gs1000g charging problem

[Quintin Snell]

Ok, ive read the stickies, and looked at a couple of other threads, and sort of understood some of it. They didnt seem to really address my problem, so i will put it out there for assistance. (I wish i had been on this site when re-built the suzuki...)

Im only actually going to be able to work on the bike in 6 weeks, but i want to post this now, so it is here, while still remember, before i get stuck into my new build... also it gives me time to read up on what needs to be done...

my issue is this: my bike drains the battery (brand new, correct rating for the bike) within 2 days, running or standing (standing takes about 5 days). It is easer to start when warm, when the battery is too flat for electric start, it is still really easy to jump start. (Good thing, as it happens often). If the battery is under 12.5 volts, the starter doesnt swing enough to start the engine and eventually runs the battery down to the point where all i get is the strangled clicking noise of the solenoid trying to do its thing. (Lights are off, gears in neutral) Starter was recently reconditioned. All electrics are standard, i was using a double wattage globe for better white light, but took it out and put the orginal back. 2 mechanic types have checked my system and said it is fine, i followed the stator papers in the gs resources and got the same result. The bike, however, tells me there is a problem somewhere. Whew, i think that is everything.

So far, my plan of attack is this... i assume the charging system itself is ok, seeing as 3 different sources say its ok. (So why does it discharge while standing...)

Firstly, learn how to use my multi meter properly.

The bike wont start at 12.5 volts or less, so i will check the starter is good. (How do i do this? I have a spare, so want to check both, if one is shot i can use the other, or send it for reconditioning again.) Surely 12.5 volts should be good? (I know amperage plays a part here, but i had the battery checked and it is good)

Check my coils are good (follow procedure in sticky, thanks Sonreir ☺)
what else do i need to do?

Thanks in advance for helping me with this long standing irritation. Also, im sure I'm not doing my battery any favours by charging it in the workshop every 2 days... i replace my gs battery every year and a half, the gtr battery lasts almost 5 years. Suzuki battery comes out the bike when im away, so is only actually in the bike about 4 months a year, kawa stays in permanently. I used to have an optimiser on the suzuki, when not in use, but it was stolen off my bike one night.. so wont get another till i have a decent lock up...

 

[Sonreir]

Sounds like you have a power drain when the bike is off. Easy to verify, but it can be very hard to trace.

First step, disconnect the negative terminal of the battery and using your multimeter, measure the Amps between the disconnect terminal and the battery. You should get zero Amps.

Assuming that checks out, the problem (or at least part of the problem) is a dead or dying battery. Yeah. Even if it's new.

Next, check the actual charging. Get the bike running and warmed up and measure voltage across the battery terminals. You should get around 12.5V, but a bit higher is better. Now, rev it up to 4000 RPM and you should be seeing about 14V, sometimes around 14.5V. Anything above 14V is OK, but it should definitely stay under 15V. 14.3V or 14.4V is ideal.

 

[Quintin Snell]

Thanks for this, i have checked the battery at stop, low revs and high revs, all looked good (part of the gs forum stator papers checks, designed to test stator and r/r, and by association, charging rate) .i havent tried checking the amps between neg and battery, will give it a shot. When charged on my work bench, battery holds just over 13 volts. This is my second new battery, the first came from the shop with a dead cell. I have had this one checked out, apparently it is fine.
i have suspected a power drain for a while, but as you say, very difficult to trace the culprit...
I will re check running voltages again when I'm home. Cheers ☺

 

[High On Octane]

My '83 GS550 used to eat stators and rectifiers. I later found out after I traded it that this a common problem on the early GS'. The remedy seems to be to run a ground wire directly from your battery ground to the ground wire on the rectifier. One of my old customers at Advance Auto owns 6 different 80's GS1100's and was the one who recommended the ground wire to me, claims all 6 of his GS' have no charging problems now. I never got a chance to implement it, but I did research it thru Google and found others who have done the same thing.

 

[cxman]

i have also just tossed the old factory reg/rectifier and used a mofset one

http://www.roadstercycle.com/

 

[nategs550]

What they said. The stock R/R is is garbage. I switched to a MOSFET R/R with all ground wires going to a single point with another wire leading to the negative terminal on my GS550E. Had 0 problems in the last two years with it.

 

[Quintin Snell]

Thanks guys, i will check these tips out. Ive been scratching my head over this for too long now. 2 different shops have given me the thumbs up after sending it for testing, but the pike has different ideas... 2 days of runabout riding, battery is flat, so i thought, maybe i wasnt ririding far enough to charge up, but after a 50km ride, the starter barely turned over, had to push start. Lickily she starts really easily in first at not much more than a walking pace...

 

[Sonreir]

Fun fact. A Honda CM400/CM450 R/R will hook right up to a GS with a bit of wiring changes and they're a lot cheaper, too.

 

[Quintin Snell]

Thanks, i have heard about the honda rr mod, apparently its a lot more reliable too, something about a difference in phases... i need to figure that one out, i have a mate at home who can help me with that