still have a dead(?) cylinder

[dale914]

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[MaxMidnight]

Without wishing to state the bleedin' obvious, you need three things to get a motor to run.
1 - Air and fuel mixed at the appropriate ratio.
2 - A spark at the appropriate time
3 - The air/ fuel mix to be compressed.

If there are differences between cylinders then that can cause the misfire or temperature differential.

Are you taking the reading across the rev range or at (say) tick-over?
If only at one engine speed then you are not taking into consideration the potential changes to air/ fuel ratio between the idle circuit, need and main jet.

Start with a compression check, then close inspection of the coil(s), HT lead(s), plug cap(s) and plug(s).
Try moving the LH system to the RH and see if the problem moves. If it does then you have narrowed down where the problem lies and if not (and the compression is OK) then it must be a fuel related, probably running too rich. Check the idle mixture setting, needle position (if adjustable) and main jet is the same as the other three, check float height.

One other possibility is that the material thickness of #1 header is greater than the rest so less heat can escape?

 

[dale914]

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