KMX125 Cutting out when warm

[Captain Liberious]

Hi fellas,
I've got a KMX125 field bike that runs great until its warmed up, then it cuts out and wont start again for a few minutes.
I think this may be down to a faulty ignition coil, I was wondering if anybody knew how much resistance these should have?
I'm reading around 17000ohms when cold, I've got it sat on a heater now but cant see any noticeable increase in resistance.
One thing thats strange is that the bike will start easier if I pop the choke on, which is weird seeing as the engine's hot. Get it to rev once and I can knock the choke off and it'll run fine for a couple of minutes then bog down and cut out again.
The bike was definently running lean, could this have affected it in this way?
I've got some sealant setting on the inlet manifold which was perished, and I've sealed up the hole from the oil pump which I dont use, so that should hopefully cure that problem.
Any thoughts very welcome!
Cheers
____________________
A squid eating dough in a polyethelene bag is fast and bulbous, got me?

[Ariel Badger]

Fuel tank vent blocked, run it with the cap off.
____________________
Bikers make great organ donors, get 115 on your licence today.

[Compo]

Primary Coil Resistance ( Conector to connector ) Should be measure on the x1k range and give between 0.153-.0207

Secondary Coil Resistance connect between ht lead ( Spark plug cap off and terminal that would have the black/yellow lead ) Should give you 3.84 -5.76