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hey guys am in the process of learning to reading and understanding what a spark plug shows when tuning a moto.

i understand the theory behind what am looking at but i keep questioning my self about something.

now i understand how to read the jetting for rich or lean and just correct for a moto but am stumped when i try to put the knowledge of reading the correct heat range for a moto n the correct timing for a moto from a plug as these both are in the same place..

in the first image they show an example of the heat range being to cold.now i would like to know whats stopping me from thinking that the engine could take more timing at that rpm (until it meets the bend)...

am confused ...i would like to know if u change the heat range one step hotter will that mark on the plug move closer to the ground strap..

if it does ,does this mean optimal timimg changes with different heat range .

i ask for one simple scenario...say am tuning a 700hp car and the owner bought plug for that level ..while am tuning around 450hp should the plugs show too cold or would it read properly..

my second image show whats suppose to be optimal timing at wot..

Alain K

You normally adjust the heat range when using forced induction. To lessen the affect of pre-igintion ( detonation) by having less chance of hot spots that will prematurely ignite the mixture. Also running a colder plug lessens the affect of spark blow out since the center electrode is more "protected".

It seems like you might be confusing 2 things with each other. What are you trying to accomplish?