GS1000G Ignition coils

[Sudds]

I have been unable to get my GS1000G to start without spraying in carb cleaner into the airbox. And then it will only run for a short time. Have totally eliminated carb as the problem. Checked the coils and got 4 ohms on the primary and 11,000 ohms on the secondary. Acording to my manual the secondary should be 32,000. The coils spark but the spark is thin and appears weak. I have read the listings about going to Dyna coils. The green coils are 3 ohm coils and the standard coils are are 4 ohm coils. Will this difference cause the new Dyna coils to overheat and fail prematurely?

[Nessism]

Lots of people around here using those green dyna coils without issue. The stock coils are rated between 3 - 5 ohms so green should be fine for the ignition system.

[BassCliff]

Greetings and Salutations!!

Hi Mr. Sudds,

Your mission, should you decide to accept it, is to read your "mega-welcome" and make sure the maintenance check lists are followed to the letter. This post will self-destruct in 10 seconds.

But seriously, clean carbs, adjusted valves, air intake system with no leaks (do you have the airbox installed?), clean electrical connections and grounds, etc, are vital. All the systems are interdependent. OK, ok. I'll shut up now and just say "Howdy!"...

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", the Carb Rebuild Series, and the Stator Papers. Now let me roll out the welcome mat for you...

Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[salty_monk]

I have an odd (1) stock 1000G coil that works well. Needs some new leads in it (I have pulled the old ones out so stick new ones in & a bit of silicon to seal).

If you're interested let me know...

Dan

[Steve]

How is it that you have "totally eliminated carb as the problem"? Details, please.

Next, get rid of the starting fluid, carb cleaner, whatever you use to spray in the carbs to get it to start.


Two things come to mind for situations like yours.
1) Hard starting when cold can be caused by tight valves. When were they last adjusted. If if don't know, it's past time to do it.

2) Unless you can convince me that you have stripped the carbs down, dipped each of them for about a day, and re-assembled them with new o-rings, I will keep pointing at the carbs as your problem area.

So, please, ... tell us what you did to "totally eliminated carb as the problem".

.

[Sudds]

Thank you for your response.

The valve clearance was checked less than a 300 miles back.

The carbs have not been completely dissambled. But the inrichment circuit is completely clear. The o rings have been replaced around the shut off valve seats. All other chanels have been checked and are completely clean. The bike has always been inside and has only 32000 miles on it.

The reason I am asking this question is because the coils do not check and the spark while starting with a charger connected apears very weak. And the secondary side of the coils has only one third the resistance that it should have. Now that tells me the coils are not putting out the power that they should. Am I wrong in this thinking?

[rustybronco]

Primary side of the ignition coils 4 ohms... Okay

Secondary coil resistance measured without the plug caps (boots-plug ends-ect.) 11-13K ohms... Okay.

Good spark plug cap resistance 5K ohms (measured independently)... Okay

resistance values above these measurements require further investigation.

what is the voltage measured at the coils?

[Sudds]

THanks for your data on the coil resistance. But my shop manual that I purchased when the bike was new shows that the secondary should be 31,000 to 33,000 ohms. Mine are only 11,000 which tells me I have a very weak spark which appears to be the case when doing the finger test and acutually observing the spark. And yes the plug caps are removed. Before I go any further with anything else such as the carbs I really need to resolve this issue. I don't want fix something else that isn't broke.


Thanks
Sudds

[rustybronco]

Then don't replace the coils because of the 11k secondary resistance value.

first thing to check is the voltage @ the coils.

second, what is (are) the plug cap resistance(s).

[Sudds]

Two of the plug caps were completely open. All plug caps were removed. Plug wires are going directly to plugs. I will check voltage to coils. Not sure how to do that other than turn on ignition and measure voltage across the two coil contacts. When in the past attempting to start I always had a charger hooked up to assure full system voltage. The plugs are brand new NGK as required per manual. This same plug has always performed great and from everything I find I have the correct plug, non resistance.

Thanks much for your help.

Sudds

[Octain]

Are the plugs new(B8ES)? Even if they look ok they can be fouled. Replace the plugs, plug caps and wires. If you wanna replace the coils then more power to ya, do it.
If you do this and still have problems I would guess the carbs need cleaned, and all of the o-rings replaced according the the carb page on Cliffs site. Even if they look clean. Its not that tough to do.
Trust me, these guys know these bikes.

Keep us posted.

[sscott]

Should you also test the ignitor unit to see what is comming from that?

[LarryA_Texas]

I have been unable to get my GS1000G to start without spraying in carb cleaner into the airbox. And then it will only run for a short time. Have totally eliminated carb as the problem. Checked the coils and got 4 ohms on the primary and 11,000 ohms on the secondary. Acording to my manual the secondary should be 32,000. The coils spark but the spark is thin and appears weak. I have read the listings about going to Dyna coils. The green coils are 3 ohm coils and the standard coils are are 4 ohm coils. Will this difference cause the new Dyna coils to overheat and fail prematurely?

Put a volt meeter on the positive lead to the coil with the other (black) end grounded and turn on the ignition switch. Battery voltage has to pass through a lot of old/corroded/dirty connectors before it gets to the coil. Each of these can cause a drop in voltage. There's the kill switch, the ignition and several connectors in between. All of them should be clean and tight. A possible alternative is the relay mod posted elsewhere in this forum.

If you have a battery voltage of 12 or so, and voltage of 6 or 7 at the coil, there's your problem. It's hot enough to ignite starter fluid but not enough to light off gasoline. If the voltage seems reasonable then you are back to the carbs. These bikes are very sensitive to air flow and a bad o-ring or bad seals at the airbox can make a huge difference in how it starts and runs.

Every bad coil I've seen has had bad ohm readings on the primary side. I'm sure there are many ways for them to fail. I just haven't seen it.

If you're sure about the voltage and happy with the carbs then switch the coils with a known good set. Maybe you know someone nearby that will let you borrow a set. If that won't happen then you can buy the dynas.

My bet is it's the carbs.

[Octain]

My bet is it's the carbs.

Ditto.......

[rustybronco]

Two of the plug caps were completely open. All plug caps were removed. Plug wires are going directly to plugs.

Which two showed showed no resistance? 1 and 4, 2 and 3, or????

what do you mean by "plug wires are going directly to plugs". do you mean they are connected directly to the plugs without the plug caps?