What to look for? Cylinder not getting spark

[doocatiboy]

My 93 750 SS vertical cylinder stopped running due to lack of spark. Front cyl fires/runs ok. I checked the contact under the plug cap and cleaned it with a dremel wire brush so it's not rust or other fester. New plugs so it's not the plug either. Ground is solid, too.

What's my next step to determine where the fault lies?

Thx

[Ducman851]

Try swapping the ign boxes to see if the fault moves. If not possible pickup coil issue?

[doocatiboy]

Thanks Ducman. The coils are the two grey cylindrical jobs mounted to the air box between it and the battery correct?

[doocatiboy]

Disregard last question thanks.

[El Gladiateur]

Pretty sure one of your ignitions boxes is shot.

[doocatiboy]

Not sure what you mean by 'ignition box' (coil?) but it was in fact the pickup along the flywheel. Replaced and good to go.