Bundy...

Under power... Air leaks

Wiggle the crank shaft, if it moves, your bearings are gone.
Check your fuel tank, if it's not providing pressure it will lean out
Check your Carby, if it's seated well, and the boot has no cracks or holes
Check your head and ensure it's clean and seated without pressure loss
(Put your ear up to it and turn t over by hand)
Check fuel lines for holes.
Check exhaust system for leaks.

If at idle..
Check your glow plug is seated and in good working order
Check your clutch after warmup and ensure it's not binding etc
Thrust bearing and clutch bearing could be stalling engine
Use a rubber band to retract the carby to ZERO and check your servo settings.


If all the above ok..
Warm the engine with a hair dryer etc.
Set a max 1mm Idle gap and then richen the top needle a whole turn
Try to start engine and lean the bottom needle until it does.
You may have to remove the plug and clear the flood if it's too rich
You should get to the point of an idle that lasts around 4 second before richening.
Gently throttle 1/8th the way and work the top needle without revving too high
Get a manageable top richness and set it on track.
Don't run it too rich nor too lean until it warms up then set the top needle slightly rich to ensure good fuel pressure.

Warmed up and circulating...

If the car over runs as you come off power after a long straight, you need to reduce the idle and lean the bottom a little more.
If the car comes off power well and drops to an idle nicely, then tune top to lean with trail of fine smoke, not too much as you cant compress liquids.

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PS: AT Platinum is awesome fuel!