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Could somebody clarify something in the manual for me?
On page 190 of the Clymer manual chapter on electrical system, describing how to diagnose 'weak or no spark', it says:

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"Continuity test
2.
Use an ohmmeter set at Rx1000 and measure between the 2 secondary leads (spark plug leads) with the two spark plug caps in place. The spec R is 21 to 28 Kilo-ohms."

3.
Use an ohmmeter set at Rx10 and meaasure between the two secondary leads (spark plug leads) with the spark plug caps removed. Spec R = 13.6 to 15.5 ohms"
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Does this mean that the resistance between these two (spark plug) outlets on the coil (as shown in the photo) should have a resistance of roughly 14 ohms? Because I measured both and they're 14 kilo ohms (14,000 ohms). Are they both shot?

Also - how do you measure the resistance of the spark plug leads without specialized gear? I tried shoving little nails into the lead holes and I got resistances of 8,600 ohms for one, and 156,000 ohms on another but the other two didn't show any connectivity at all. This could be simply because the little bits of wire weren't making contact, though.

Did you clear out the jets? Make sure you could look all the way through them?
If it ran with ether then it should run with gas, sounds like it still isn't getting any or much though. Might want to pull the plugs and see if they're getting wet.

Wrider wrote:Did you clear out the jets? Make sure you could look all the way through them?
If it ran with ether then it should run with gas, sounds like it still isn't getting any or much though. Might want to pull the plugs and see if they're getting wet.

+1

I think Wrider is on the right track here.

After the bike fires up with the starter fluid, can you keep it alive by revving the throttle? Or does it die instantaneously after the shot of starter fluid burns off? If it dies instantaneously and you cannot keep it alive by revving it, it's very likely a problem of the engine not getting enough gas to stay running.

Wow I think this is the first time I have ever seen anyone start a thread asking a question then after people post suggestions, completely edit the original post to ask a completely different question...

tomfrombc wrote: Also - how do you measure the resistance of the spark plug leads without specialized gear? I tried shoving little nails into the lead holes and I got resistances of 8,600 ohms for one, and 156,000 ohms on another but the other two didn't show any connectivity at all. This could be simply because the little bits of wire weren't making contact, though.

Doen't your multi-meter have the long needle-like prongs for this?

Whoa completely different post than I replied to.
For measuring what you have in the picture I'd recommend you put the plug wires back in, and take off the spark plug caps. That should be about 14 Kohms. When you have the wires AND caps in place it should be 21-28 Kohms.

sorry about the editing - not sure what happened there.

Thanks for the responses.

Um, but I don't get what they mean by 'spark plug caps' - does it mean the wires that go from the coil to the spark plug? As far as I can see, theres the coil, the wire going to the plug and thats it, no separate "spark plug wire" in addition to another 'spark plug cap'.

No, the multimeter prongs dont make contact - I had to shove a wire in it, even then the R was either 160k, 8K and could get no readings on the others at all (open circuit).

You guys see the photo now, right? I measuerd the R between the two contacts (in the p[ic) and the R is 14K on both - is this normal?

The problem cant be just lack of fuel - I gave it ether and it still didnt run.

I checked for spark and one cyclinder had weak spark, the rest none.

I replaced the plugs and nothing still.

I followed the manual for testing the pickup coils and they're fine -330 ohms each as spec.

so it has to be either spark unit or coils or spark plug leads from coils to spark plugs, no?

Go to the Shoe-Box Autoparts store and buy a set of plug wires for any 4 cly and replace yours. Spend a little extra and get 8mm plug wire in yellow or red, but you have to trim it to fit the coil end.