Batterry question...

[C.V.]

Hi everybody,
Newbie from San Diego here and you'll find it hard to believe, but I have charging problems with my '79 GS 850. I've been all through the stator papers, everything checks out via the flow chart, installed new electrex RR, hard wired al connections, double checked and checked again all grounds, stator reads 76 volts at all 3 leads, 1.1 ohms on each coil, but I'm still only getting about 13.1 charging volts at the batterry. I keep the battery topped up on a batterry tender jr. fully charged it reads about 12.98 volts. Blah blah blah... heres my question - Could a bad battery cause the low charging voltage reading? It seems to me that even if the battery is bad, I should still see full charging voltaqge, since this is a function of the stator/RR system.

Any help you could give me, uh, would be very, uh, helpful...

[earlfor]

Yes, a bad battery will alter the charge rate. In some instances where the battery is very bad, it will not accept any charge rate and the charger when connected will surge, show zero volts, and then shut down. However, if your charger charges the battery to 12.98 volts and the battery will hold that voltage overnight, then the problem is not your battery.

Earl

Hi everybody,
Newbie from San Diego here and you'll find it hard to believe, but I have charging problems with my '79 GS 850. I've been all through the stator papers, everything checks out via the flow chart, installed new electrex RR, hard wired al connections, double checked and checked again all grounds, stator reads 76 volts at all 3 leads, 1.1 ohms on each coil, but I'm still only getting about 13.1 charging volts at the batterry. I keep the battery topped up on a batterry tender jr. fully charged it reads about 12.98 volts. Blah blah blah... heres my question - Could a bad battery cause the low charging voltage reading? It seems to me that even if the battery is bad, I should still see full charging voltaqge, since this is a function of the stator/RR system.

Any help you could give me, uh, would be very, uh, helpful...

[tkent02]

Just curious, what are you using to measure these 13.1 volts?

A meter with a good battery in it I hope?

Low batteries in some multimeters can cause inaccurate readings.

[C.V.]

I bought the meter and the battery new for this problem, so the batt. should be good...but ther meter is a cheap one, 20 dollar digital from the 'ol shack, but it has worked fine for everything so far. Maybe i got a defective RR from electrosport? Could the stator check out fine on all the tests and still be bad?

[BassCliff]

Hee Haw2 Howdy!

Hi Mr. C.V.,

Have you run the ground wire from your regulator/rectifier directly to the negative terminal of the battery? Have you cleaned all of the electrical connections and grounds on the entire bike? All new fuses? Have you tried a new r/r? Have you eliminated the wires that run to the (usually) non-existent headlight switch and connected all three stator outputs directly to the r/r inputs? Much more information awaits you in your very own mega-welcome! \\/

Dear fellow GS rider,

Let it be known that on this day you are cordially and formally welcomed to the GSR Forum as a Junior Member in good standing with all the rights and privileges thereof. Further let it be known that your good standing can be improved with pictures (not you, your bike)!

Perhaps you've already seen these, but I like to remind all the new members. In addition to the carb rebuild series, I recommend visiting the In The Garage section via the GSR Homepage and check out the Stator Papers. There's also a lot of great information in the Old Q&A section. I have some documentation on my little BikeCliff website to help get you familiar with doing routine maintenance tasks (note that it is 850G-specific but many tasks are common to all GS bikes). Other "user contributed" informational sites include those of Mr. bwringer, Mr. tfb and Mr. robertbarr. And if your bike uses shims for valve adjustments, send an email to Mr. Steve requesting a copy of his Excel spreadsheet that helps you keep track of clearances, shim sizes and other service work.

These are some edited quotes from one of our dear beloved gurus, Mr. bwringer, with ideas on basic needs (depending on initial condition), parts, and accessories.
***********Quoted from Mr. bwringer************
Carburetor maintenance:

Replace the intake boot o-rings, and possibly the intake boots. Here's the procedure:

http://bwringer.com/gs/intakeorings.html

Here's an overview of what happens with this particular problem:

http://cycleorings.com/intake.html

You'll also want to examine the boots between the carbs and the airbox. There's a good chance these are OK, but check them over.
And finally, if things still aren't exactly right, you'll want to order a set of o-rings for BS carbs from the GS owner's best friend, Robert Barr:
http://cycleorings.com
Once you receive these rare rings of delight, then you'll want to thoroughly clean and rebuild your carburetors. Here are step-by-step instructions that make this simple:

http://thegsresources.com/gs_carbrebuild.htm

***********************************
Every GS850 has (or had) a set of well-known issues that MUST be addressed before you have a solid baseline for further troubleshooting. It's a vintage bike, and it's quite common (as in, every single GS850 I have had contact with) that there are multiple problems that have crept up and slowly gotten worse over the years. It's not like a newer vehicle, where there's generally one problem at a time.

These common issues are:

1. Intake O-rings (install NEW OEM or Viton only - common nitrile O-rings will quickly deteriorate from heat)
2. Intake Boots (install NEW -- these cannot be repaired)
3. Valve clearances (more important than most people think)
4. Carb/airbox boots
5. Airbox sealing
6. Air filter sealing
7. Petcock (install a NEW one)
8. On '79 models, install new points or Dyna electronic ignition (or at least verify that the old points are working correctly)
9. On all models, it's fairly common to have problems with the spark plug caps. These are $3 or $4 each, and often worth replacing if you're keeping the stock coils/wires.
10. Stock exhaust with NO leaks or holes -- good seals at the head and at the junctions underneath.
***************************************
OEM Parts/Online Fiches:

I would definitely double and triple the recommendations to use Cycle Recycle II and Z1 Enterprises as much as possible. These guys are priceless resources. Z1 tends to have slightly better prices, CRC2 has a wider range of goodies available. If you're near Indy and can bring in an old part to match, CRC2 has a vast inventory of used parts.
http://denniskirk.com - Put in your bike model and see what they have.
http://oldbikebarn.com - seems to be slowly regaining a decent reputation, but it's still caveat emptor. They don't have anything you can't get elsewhere at a better price anyway.
http://www.babbittsonline.com/ - Decent parts prices. Spendy shipping. Don't give you part numbers at all. Useful cross-reference if you obtain a part number elsewhere. Efficient service.
http://bikebandit.com - Fastest. Middlin' prices. Uses their own parts numbering system to obfuscate price comparisons -- can be very confusing for large orders. Cheapest shipping, so total cost usually isn't too bad.
http://flatoutmotorcycles.com - Slow. Cheapest parts prices, crazy shipping costs. Don't expect progress updates or much communication. Real Suzuki part numbers.
http://alpha-sports.com - Exorbitant parts prices. Different type of fiche interface that's quite useful at times, especially with superceded part numbers. Real parts numbers. Shipping cost and speed unknown due to insane, unholy pricing.

Stainless Bolts, Viton o-rings, metric taps, dies, assorted hard-to-find supplies and materials, etc:

http://mcmaster.com - Fast, cheap shipping, good prices. No order minimum, but many items like bolts come in packs of 25 or 50. Excellent resource.
http://motorcycleseatcovers.com - Great quality, perfect fit (on original seat foam), and available for pretty much every bike ever made. Avoid the textured vinyl -- it's perforated.
http://newenough.com - You DO have riding gear, don't you? Great clearances, always outstanding prices and impeccable service.
***************End Quote**********************
Additional parts/info links:

GSR Forum member Mr. duaneage has great used upgraded Honda regulator/rectifiers for our bikes. Send him a PM.
New electrical parts:
http://stores.ebay.com/RMSTATOR or http://www.rmstator.com/

http://www.ricksmotorsportelectrics.com/index.php

http://www.electrosport.com/

For valve cover and breather cover gaskets, I recommend Real Gaskets (reusable silicon):
http://www.realgaskets.com
The Rice Paddy (salvage/used)
http://www.ricepaddymotorcycles.com
Carolina Cycle
http://www.carolinacycle.com
Ron Ayers Motorsports
http://www.ronayers.com
MR Cycles
http://www.mrcycles.com
Moto Grid
http://www.motogrid.com
If all else fails, try this:
http://www.used-motorcycle-parts.org/
Used bike buying checklists:

http://www.amadirectlink.com/roadride/Riderresc/checklist.asp

http://www.clarity.net/~adam/buying-bike.html
Lots of good info/pictures here:
http://www.suzukicycles.org

http://www.cyclechaos.com/wiki/Motorcycle_Wiki

Thanks for joining us. Keep us informed of your progress. There's lots of good folk with good experience here.

Thank you for your indulgence,

BassCliff
(The unofficial GSR greeter)

[psyguy]

welcome aboard

i would start by thoroughly cleaning all connections and testing the battery to see if it holds charge
these are the two pre-requisites for a sucessful stator and r/r diagnosis

[C.V.]

all the connections are brand new, redone when i put in the new RR in, all soldered and shrink wrapped. The battery holds its charge fine, just has a slow voltage drop over time, hence the need for the battery tender. There doesn't seem to be any static drain.

[Killer2600]

Are you getting 13.1 at idle with a fully charged (before you started the bike) battery or are you getting 13.1 at a higher rpm? If it's the former of the two then I would suspect that everything is ok, these bikes don't really do any charging at idle.

[tomm]

Are you getting 13.1 at idle with a fully charged (before you started the bike) battery or are you getting 13.1 at a higher rpm? If it's the former of the two then I would suspect that everything is ok, these bikes don't really do any charging at idle.

I was thinking along the same lines. Need to know what else is on and what rpm.

As you increase rpm from idle, you should see the voltage increase. At some point, you should see the increase stop and even drop back a little bit. This is the point where the regulator kicks in. For my bike, I see that occur at 14+ volt range before I hit four thousand rpm. I typically test with everything off, including the headlight. Usually don't see much above 13+ volts with the headlight on at the same rpm. Charging system works fine and battery is always fully charged when I go to start the bike.

Suppose your regulator could be kicking in early, but not something that is very likely. No way to measure that directly other than above.

Other thought is if your R&R has a separate wire for a reference voltage, where is that connected to and what is the voltage there.

[C.V.]

It hits 13.1 at about 2500 rpm, and doen't go any higher, with lights on or off. It never gets anywhere near 14 volts. 13.1 isn't really enough to keep it charged up is it?

[tomm]

Bottom line is with no load (headlight off) at 5000 RPM, you should have at least 14 volts. If you don't, then something isn't right. Yet it sounds like everything is working OK, other than the measurement itself and the slow drain that you mention. If it wasn't for that drain, I'd be thinking that everything is fine and just ride it.
How slow is the drain? I've let my bike sit for a month or more and it still starts right up. You shouldn't need to keep it sitting on a tender if you are riding it fairly regularly.
The slow drain would suggest to me that either the battery is bad or the regulator is bad (diode leaking).
Try disconnecting the R&R from the battery the next time you leave it sitting for a while and see if the battery has drained the same way it did in the past for you with the R&R connected. If it hasn't, your regulator is likely faulty. If it has, it's probably your battery.

[C.V.]

Went through the whole process again, and now its a little better. About 13.4 at idle, and 13.8 at 4000 rpm. Considering the margin of error with my $20 radio shack meter, i think I'm pretty close. I'll run with it a while and see how she holds up. THANKS EVERYBODY FOR YOUR HELP!! So much I wouldn't have gotten done without this website THANK YOU!

[tomm]

Went through the whole process again, and now its a little better. About 13.4 at idle, and 13.8 at 4000 rpm. Considering the margin of error with my $20 radio shack meter, i think I'm pretty close. I'll run with it a while and see how she holds up. THANKS EVERYBODY FOR YOUR HELP!! So much I wouldn't have gotten done without this website THANK YOU!

With those numbers, I'd say you're good to go. Ride safe and let us know if anything changes.