need help with my 1981 gs750l

[wolfs1966@hotmail.com]

The problem that i,m having is when i have the bike running and the headlight on with the turn signal on the headlight dims when the turn signal blinks and when i turn the bike off and try to restart it . it acts like the battery is drained down to where it won,t start . i was wondering if it was the starter relay or something else ? any help would be great . PS the battery is new and fully charged .

 

[mortation]

The problem that i,m having is when i have the bike running and the headlight on with the turn signal on the headlight dims when the turn signal blinks and when i turn the bike off and try to restart it . it acts like the battery is drained down to where it won,t start . i was wondering if it was the starter relay or something else ? any help would be great . PS the battery is new and fully charged .

When the bike is running did you test the terminals for the battery with a multi meter?

 

[wolfs1966@hotmail.com]

I did test the battery and it was showing 11.6 volts .

 

[posplayr]

battery Charge

battery Charge

>>>>PS the battery is new and fully charged .

>>>>I did test the battery and it was showing 11.6 volts .

The first statement is now incorrect.

Sorry for being so terse. Without knowing anything else I would have to guess that the current required to run the blinker is more that the bike is putting out at idle. Als since your battery is now discharged and you were running the bike is further evidence your bike is not charging. When you idle the bike up does the blinker still dim the head lights? If so further evidence you are not charging.

You are cordially invited to review the stator pages and figure out why it is not charging.

After recharging your battery, do a simple test of measuring the battery voltage:
1.) battery before running engine (should be about 12.8-13.0v)
2.) battery at idle (should come up to about 13.2-13.5)
3.) battery voltage at 4000 RPM (If I remember the specs 14.5-15.0v)
4.) battery voltage off (back down to 12.8-13.0 or slightly higher)

If it doesn't do this then it definitely is not charging and go to the stator pages.


Posplayr

 

[mortation]

The bike was running and you were getting 11.6 volts between the two terminals? I dont think thats good. It should be over 13 volts, 14 or 15 if I recall as it has to charge the battery. If its not doing that you could be running off the battery which is why it keeps killing the battery.

 

[wolfs1966@hotmail.com]

ok here,s the new problem when I turn the blinker on and hit the horn the tone goes high then when the blinker blinks the tone drops and then back up again it only does it when the blinker is on . Could it be grounding some where ? I,m wondering if thats causing the power drain consdering that,s the only time the battery acts like it is draining down .

 

[posplayr]

When in doubt measure it.......

When in doubt measure it.......

As I recall that is one of the members famous quotes.

>>>>>ok here,s the new problem

If your bike is not charging and so you are running strictly off of the battery then anything you do to load the battery will effect anything else that is already running off of the battery.

You will probably also note that the tail lights dim the head light and the tail lights get dimmer when the blinker blinks.

It is all the same problem, no charging. A healthy charging system would easily supply the necessary power especially if you revered it a bit.

>>>>Grounding problem????
Yes it could be and Please refer to the stator pages.

If there is a quick fix to this problem it will only come from doing some basic measurements as indicated. Anything else is stabbing in the dark [-o<.


Posplayr

 

[twistedwankel]

The problem that i,m having is when i have the bike running and the headlight on with the turn signal on the headlight dims when the turn signal blinks and when i turn the bike off and try to restart it . it acts like the battery is drained down to where it won,t start . i was wondering if it was the starter relay or something else ? any help would be great . PS the battery is new and fully charged .

If your bike were brand new in 1981 the headlight would dim with the blinkers on sitting at a light in traffic.

I used the stator papers to determine that my stator was bad (HEY IT'S AC with no ground) on one leg and replaced it with a used one (I'm somewhat ashamed to say) because it was cheap and is still working I also had an occassion where the "new" battery from Advance Auto was junk and put the old one back on the bike which worked much better when fully charged.

Clean ALL your connectors on the bike.

 

[chuckycheese]

I feel certain that many people on the forum have replaced electrical parts that were perfectly good..(I'm pretty sure I have, too). It's easy to get 'caught up' with the idea that something's wrong that isn't; it's also expensive, so, save your discarded parts for a time when you're better informed.8-[

By the way, this isn't directed at this particular problem but, rather, a general comment; I just think it's very easy to become convinced that an electrical part must be bad...that isn't.

 

[almarconi]

I feel certain that many people on the forum have replaced electrical parts that were perfectly good..(I'm pretty sure I have, too). It's easy to get 'caught up' with the idea that something's wrong that isn't; it's also expensive, so, save your discarded parts for a time when you're better informed

Sometimes when troubleshooting problems this can be difficult to avoid. If you've got several components it can be hard to figure out the problem unless you know that you have at least one good component. I had a problem with my volvo, the car would stumble above idle to the point that the car was not driveable. I narrowed the problem down to the fuel system by checking the diagnostic codes. Several of the components in the fuel system could have caused the problem..for me it was easier to replace all the components rather than spending hours and hours trying to pinpoint the defective component.

 

[posplayr]

Twistedwankel

Twistedwankel

I went into the garage to try that out. It is not back to 1981, but I think my chargings system is running pretty close to spec even though it does have a new Electrosport Stator but OEM R/R.

The bike barely provides enough power at idle without the lights on and with the headlights on the idle voltage was less than when he engine was off. Interestingly even though my batt would go over 14V by about 3500 rpm, I was till seeing dimming in the headlight with the blinker.

Well as indicated earler, measurement is better than conjecture and I don't think headlight brightness in this instance is close enough to the relevant factors.

Nice point.

Posplayr

 

[BassCliff]

Hey howdy hey!

Hey howdy hey!

Hi Mr. wolfs1966@hotmail.com,

Please read through the Stator Papers (link below) to become familiar with the GS charging system and troubleshooting procedures.

It sounds like you have a charging problem. With these classic bikes, it's always a good idea to go completely through the wiring harness, from headlight bucket to tail light, and clean all of the connections (bullet connectors, etc). Then run a dedicated ground wire from the regulator/rectifier unit directly to the negative terminal of the battery. Then retest the battery voltage while idling around 3000 to 4000rpm. If you read less than 14v then test your stator. If the stator is good then you might have a bad r/r. Follow the Stator Paper troubleshooting guide. Note that all testing starts with a known-good fully charged battery. And now, here is the world's most dangerous mega-welcome! \\/

[FONT=Arial, sans-serif]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 [/FONT][FONT=Arial, sans-serif]bike[/FONT][FONT=Arial, sans-serif])! [/FONT]

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 here 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**********************
Here are some extra 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/
The Rice Paddy (salvage/used)
http://www.ricepaddymotorcycles.com
Ron Ayers Motorsports
http://www.ronayers.com
MR Cycles
http://www.mrcycles.com
If all else fails, try this:
http://www.used-motorcycle-parts.org/
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)

 

[chuckycheese]

Sometimes when troubleshooting problems this can be difficult to avoid. If you've got several components it can be hard to figure out the problem unless you know that you have at least one good component. I had a problem with my volvo, the car would stumble above idle to the point that the car was not driveable. I narrowed the problem down to the fuel system by checking the diagnostic codes. Several of the components in the fuel system could have caused the problem..for me it was easier to replace all the components rather than spending hours and hours trying to pinpoint the defective component.

I agree! I know bike shops that work on a lot of older motorcycles will often exchange parts as a means of a quicker diagnosis.