GS550E with ND coils and Kokusan points??

[Vloukole]

Hi guys

My 1980 GS550E has a really hard time starting. Only way to start the bike is with a bump start. it will drain the battery before starting with the start button.
I have done all the maintenance I can like valve clearance, carbs cleaned with ultrasonic cleaner and new o rings. cleaned all connections, carbs sync with vacuum sync.
I also did the coil relay mod.
When I finally get the bike to start, it runs like crap. It bogs and the idle will hang and then return to normal and die. i also checked for air leaks but cannot find any using starter fluid around intake boots and carbs.
Spark plugs are always black/sooty even when using the colour tune. Stock jets
The no 1 and 4 point's are also producing a weaker spark compared to no 2 and 3 which is bright and blue.

Do you think the problem is ignition/electrical?
Is it normal to have ND coils and Kokusan Points?

 

[tom203]

Did you replace the intake boot o-rings ? If no ,see this link...

http://cycleorings.com/intake.html

the nd coils likely came with KD point setup...are primary ohms are in 5 ohm range?..try new points and condensers

 

[Vloukole]

Yes intake boot o rings was replaced.
Primary ohms at around 7.5ohms

 

[Steve]

The brand of the coils and points not matching should not be an issue. The Kokusan points (and their condensors) are not interchangable with NipponDenso points (and their condensors), but they provide the same function in the same way, so it won't matter if you have ND coils, Dynatech coils, Accel coils, or whatever you have available in your country.

How dirty were your carbs before you cleaned them? Did the bike run before the carb cleaning? If not, how long had it been since the bike ran well? How completely did you dismantle the carbs before tossing them in the tank? I have no doubt that ultrasonic cleaning of the carbs will accomplish some fine cleaning, but I have no personal experience with it, so I don't know how well it will remove the crud from SERIOUSLY clogged passages.

I am asking these questions because I have just completed rebuilding a set of carbs for another member. He recently bought the bike, so does not know any of its history, but there were no claims of carb cleaning, either chemical or ultrasonic. When they arrived, I thought he might have sent me the wrong carbs. Outside, they appeared near-perfect. Only the slightest hint of crud in a deep corner. I dropped the float bowls. Again, near-perfect. Not even a sediment line on the sides of the floats. Then the fun began. As I dismantled further, three float valves were completely plugged. Only one main jet was plugged. The needle jets (emulsion tubes) had so much crud on them, they had to be be hammered out. The slides also had to be removed with considerable force. Since all of that crud was in areas that would not be accessible without complete dismantling of the carb, I had to ask.

An engine slow to return to idle and black, sooty plugs don't usually go together. :-k
Slow to return to idle is usually indicative of a lean mixture. You have not found a leak by using starter fluid. Don't worry, I have never found a leak with ANY fluid sprayed around any of the joints. Somehow, air will still find a way in. Assuming it's a leak. It could be a simple matter of adjustment. What is the setting on your pilot (mixture) screws? When these carbs were new, they were set lean to meet emission standards, and might have been in the 1 1/2 to 1 3/4 turn range. As they have aged, and the gas formulation has changed, the setting also needs to change. I start with a rich mixture (which burns easier) by having the screws three full turns out, then adjusting them in as necessary. Most of the carbs I have adjusted end up in the 2 1/4 to 2 1/2 turn range, but each carb will be different, so don't just pick a number and set them all.

If all the adjustments are correct, it could be a simple matter of technique. Proper starting technique is to verify proper level of fuel in the carbs (PRIme, if necessary). Set the "choke" by pulling it out all the way. Turn the key ON. Pull the clutch lever (if you were "blessed" with this "safety" feature). Push the starter button. Do NOT touch the throttle. If the engine starts and races, adjust engine speed with the "choke" button. The "choke" system on these carbs relies on the high vacuum of a CLOSED throttle, so if you open the throttle AT ALL, it will not work.

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[Vloukole]

I took the carbs completely apart. everything I could remove I did. followed the tutorial.
The bike has never ran great since I bought it. I have no idea regarding its history.
I also bought new emulsion tubes.

The pilots are set at 2 turns out.
My 1000G starts great using full choke with no throttle but this GS550 wont.
The biggest issue is the bogging starting at 2000rpm up. It wont even reach 6000rpm.

 

[Vloukole]

Why is there such a big difference in spark at the points?

 

[Steve]

Why is there such a big difference in spark at the points?

There should be NO spark at the points.

Replace the condensors.

I am also wondering why your 1980 bike has points. Our last points were on the '79 models. By 1980, they all had electronic ignition.

.

 

[Vloukole]

Should I go with new points and condensors?

 

[Steve]

Examine the points. If they are clean, with sharp edges, they should be OK.

If you see sparks at the points, replace the condensors.

.

 

[Vloukole]

Thanks Steve

Could you point me in the right direction as to where I could order them from? Im from South Africa

 

[Guest]

There should be NO spark at the points.

Replace the condensors.

I am also wondering why your 1980 bike has points. Our last points were on the '79 models. By 1980, they all had electronic ignition.

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You guys over in the States got electronic ignition a year before us in the UK. My 550ET has points, a 550EX over here has electronic ignition. Can't say for certain in the case of South Africa, but it wouldn't surprise me if it was the same scenario. Suzuki liked to empty the parts bins.

 

[Vloukole]

Sounds about right.

 

[Steve]

Could you point me in the right direction as to where I could order them from? Im from South Africa

Check with member 2BRacing. He is from closer to Cape Town, but still might be able to help.

.

 

[2BRacing]

Check with member 2BRacing. He is from closer to Cape Town, but still might be able to help.

.

Thanks for the referral Steve! I checked with my local OEM dealer, and the points and condensers are available here, but at a price equivalent of about US$360 for the full set of 4 items!!!

I received a PM from the OP and have replied to him with the above information. I recommended that he change to electronic ignition from a later model GS500 or fit Dyna ignition. I have seen many posts here on GSR about such a change, and suggested he does some reading about it. I am sure it will be cheaper for him even if he has to get a Dyna system from the US.

 

[Rich82GS750TZ]

/\ /\ This is why this place is the best. GSers helping other GSers all over the world. Faith in humanity restored.

 

[Vloukole]

Thank you 2BRACING. It was a bad condensor.
Bike runs great.
It still wont start without bump starting it. The starter pulls the battery down to 8.5volts and the battery is fully charged.
It is a starter from a bigger GS. Could that make the difference in voltage drop and amps needed to turn and spark? It starts immediately when bumping.

 

[Steve]

The starter pulls the battery down to 8.5volts and the battery is fully charged.
It is a starter from a bigger GS. Could that make the difference in voltage drop and amps needed to turn and spark? It starts immediately when bumping.

The battery may be "fully-charged", but that does not mean that it's a good battery. :-k
It is possible that you have a very marginal battery and you are just charging it as much as it can handle, but it's not enough.
To test that, connect jumper cables from your car, but make sure the car is NOT running. If the bike starts well, it will be obvious that your battery is just not up to the task. Ideally, your voltage should not drop below 11 while cranking.

Surprisingly, there are very few differences in GS starters. The same part number starter works on the '80-85 450 and '81-'83 650. There is a second number that handles everything else, from the '77 400 through the '81 1000G. A third part number handles the '82/'83 750 through 1100. A fourth number is used exclusively on the 1150.

I know I have used a different starter on some of the smaller bikes, but I don't know which way I went. I might have used a 650 starter on a 1000, or it might have been an 850 starter on a 450. The only difference I noticed was that I had to add some clearance between the two mounting bolts. Other than that, everything bolted right in. I don't know what the electrical difference might be.

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