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76 f "K6" Ignition miss at #1 cylinder, no case ground, #4 is good, whats wrong?

cwyllie

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76 f "K6" Ignition miss at #1 cylinder, no case ground, #4 is good, whats wrong?

Purchased 1976er from a tool and die machinist, he loved maintaining the bike, as do I, but Im learning.
Heres the stats: This will result in a question, i promise, but you gotta know whats been checked.

Just went thru the 3000 mi routine maintenace check via the clymer manual for the first time myself.
(engine has 26128 mi/ 20-50 standard oil/ NGK d7's/100% 87 octane gas used)

Findings and Repair:
>Compression-great
>Valve clearence-great
>Timing chain- Tensioned
>Plugs- replaced new D7s
>Points and Condensers- looked brand new (but 1-4 points are slightly cupped, set to .009 to achieve 48<s of dwell vs .015 standard because the manual said measured dwell was more accurate than standard filler gauge method.)
> Timing- reset using sun gun and tach, looks great at idle and at 2500 rpm, so advance appears great
>Carbs- bowls, jets (105 mains 40 slows), floats, and stems all back to shiny new. fires right up.
>battery- New
>Charging system- charging
>Air Breather- new pods (no emissions on 76 so shouldnt change a thing)

SO all that being said, heres the "riddle", this is what its doing.

*#1 plug wire has an intermittent miss visable via the timing light. Its just suttle, just enough to catch your eye, and not predictable, the others look perfect.

*Miss is slight but detectable in the idle. theres no case ground at the boot, it doesnt shock me.
#4 does doesnt miss at all,

*Throttle revs great when pulled back ,but, slight misses when slow reved.

So Whats Failing? the points, the coil, condenser,he high tension lead?

How can I verify which component is failing, from starting at the plug and working my way back.
Is it possible to reverse the coils or the points and see if the problem follows the part? will they swap? Im pretty sure you cant swap points being as you purchase them left or right.

I dont want to just "Buy" coil packs and "Buy" points and "Buy" condensers to "Buy" my way out of a problem. I want to find the
failing part. and then go from there.

thanks for your input.
 
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