Coil question.

[ZedHead]

You could swap the coils over and see if the misfire move, that would eliminate the coil.

Just swap 2 & 3 leads over but i suspect you have a duff plug.

[DavidZ1R]

Well today I changed plug again, still not sparking, swapped 2 and 3 around, and to my great suprise still the same, no or very weak spark, changed for another coil, bugger just the same, totally baffled, by now I had run down the battery a bit so put it on charge for half an hour while I had a quick breakdown, oh and I trimmed the ht lead back 6mm, sod it I thought put it all back together, ready to consider Garry's offer , one last stab of the button, bloody thing started perfectly, after a head scratch I can only assume it was a low voltage at the battery , double checked with the colour tune and it was a lovely blue, hope that's it now.

[warren3200gt]

Would have thought battery would affect all four. HT bad connection was the more likely culprit I'd have thought. Good news either way!

[ZedHead]

Fit the relay mod if not already done

[johny brando]

Is it possible that one side of a double lead coil can breakdown, the coils on my bike are the originals, but no.2 pot keeps miss firering it pops back into the air box and sometimes the plug sparks from side to point not from tip to bend. Or could it be a pilot jet fault, have had the head off for oil leak, shim gaps all set to .15 carbs been cleaned and flushed through, it just won't tick over right and pops? Baffled.

Taking it you have tried to move the issue to another cylinder ....as prior described by another here & you have swapped over all the plug- caps -coils & the timing is correct & compression on all 4 cylinders above 120 psi gauge pressure .Well, seems like it maybe time to move back to the carbs - No intake leaks...i.e. manifold & vacuum take off's are sound ? Chokes all clear & fully operative ? Fuel levels in all float chambers are correct ....not too low ? All the Pilot system air & fuel drillings etc are 100% clear ??? as one partially varnished pilot drilling would give you trouble.
Any Zed heads nearby to you with a known good set of carbs that might step up & be nice enough to just let you borrow his & pop on em on for 10 minutes......this is just being a quicker & definitive option / way to narrow down the culprit ! .......instead of you having to spend a couple of hours stripping yours down ........at least you'd then know one way or another if can put a line through the carbs, or if your on the Money & the problem doe's actually lie within your carbs.
Good luck

[Big Fluff]

Dave. If you're going to fit new plug caps try and find some without built-in resistors.
All NGK plug caps have these and they can break down, that's why I never fit them to my bikes.
If you do fit NGK caps, treat them like a service item and change them regularly.

[DavidZ1R]

Dave. If you're going to fit new plug caps try and find some without built-in resistors.
All NGK plug caps have these and they can break down, that's why I never fit them to my bikes.
If you do fit NGK caps, treat them like a service item and change them regularly.

I might just do that Will, I must not forget to send you back those swapped shims, they did the job just fine. Thanks Will, how you keeping?