Why won’t you start!!!!!

[Desmos21]

All was running well until a few weeks ago.
A little longer to catch and then rather sputtery, with very slow throttle response. It would run reluctantly about 3000 rpm but certainly not very well. (650cc)

So I thought I’d treat it to a little refresh.
Coil, Leads, Plugs, Points, condenser, Cap and rotor, Bob weight springs, Carb base and gasket set, and an earth strap.
But now it’s dead.
I’ve got a spark but only when I give the plug a few mm gap from the earth point. Which seems a little odd. Gap was set to 0.4mm as per Marelli spec. Timing was set statically.
Thought I’d better check compression which were 80. So adjusted the tappets, now both running 110

Plugs smell of fuel but not soaked, but I’ve checked the float height and have a 10-12mm of fuel in the bowl. Jets were blown out as was emulsification tube.

So I then thought I’d check valve timing.  While the chain does appear really slack, and crank sprocket teeth are worn the timing marks align. (New chain is on order)

But currently I’m stumped. Can anyone offer a fresh angle of attack?  Please 😵‍💫

[Minijohn]

Do you have the plug leads on the correct plugs?

[Desmos21]

I’ve tried swapping to rule that out. ))

I think it’s possibly the leads I’ve made up. Perhaps they need more current than this coil produces. As I appear to be getting just a whisp of smoke from the electrode when I earth the spark plug body.

But if I give a gap to the electrode and earth of about 2mm I get a spark.

Incidentally which is cylinder 1? I thought it was rear most next to the cam chain ?

[ChrisRLewis]

Usually the spark plugs get soaked if there is an ignition fault.
Perhaps try some cold start spray in the air intake to see if there is any difference?

[Desmos21]

Thanks for the replies.
I think fuel is getting to the plugs as they are leaving a trace on my latex glove after cranking for 5-6 seconds.
I’ve ordered another set of leads as I’m sure the plugs should be sparking better than they are.

I also pulled the dizzy just to check it looked ok and all seems ok

I was wondering if a stretched chain may make the cam timing go a little wayward, despite the timing marks aligning. As I can rotate the crank more than a tooth or before the cam moves. Which I guess could also cause a slight deviation in ignition timing.
But I’m at that point where I’ve spent too long thinking and probably over thinking. 😅

[Minijohn]

Just curious - when you say you have a spark if you leave a gap between the electrode and the earth point......is that spark between the centre of the plug and the electrode or from the electrode to the earth point?

[desmos]

It’s jumping from the electrode tip to earth. Rather than across the electrode gap.
Plugs aren’t soaked or overly coked up.
And I cleaned the block for a good earth source.

I’m still awaiting the new leads to arrive so will update once they arrive.

I’ve 12v at the coil and good 12v on points operation.

Again I appreciate the replies all. 🙏

[ChrisRLewis]

Have you tried reverting back to your original coil and leads?

[Minijohn]

I'd agree with ChrisRLewis, try the old stuff again.
It doesn't sound right the spark isn't jumping across the electrode gap.

[desmos]

The king lead was displaying open circuit. Then I did a wise move and cut the original hot leads to use the sheath. That’s why I’m waiting on the new leads to arrive.

I’m hoping this is the cause as everything else is checking out.

[Minijohn]

OK, fingers crossed.

[Desmos21]

So a little update on this. I swapped the leads and had the same issue with the plugs only sparking when lifted a few mm from the earth point. But not through the electrode. So I got another pair of plugs and bingo. 
It appears the new plugs I’d fitted were duff.

Now to fix the leaking crankshaft seal from doing the timing chain. I’m beginning to think this car doesn’t want to come out of retirement. Still small progress is still progress

Thanks again for the replies.

[Minijohn]

Oh that's great news - just goes to show you can't trust new parts.

[Desmos21]

Yes sent me on a wild goose chase. Seems odd both are duff, they are from a well known supplier bu guess just one of those things. Sounds so much quieter with the new chain. I can now hear the sports exhaust.