Well I have never used a magnifying glass .. that’s a good idea.. but I think if I was on the track running a 125 or. 250 at red line for an hour or so ... I see that to get it just right for the temp .. sea level up the mountains etc ..
Or blow the motor .. and blow 3000 g ..
But after tunning 100s of 2 strokes from 76 to now .. I just never had to get that eye ball tuned in ..
my rule of thumb is simply this
If your plug Is a dark tan on a full speed under load plug chop .. assume its a mid tan .. if it’s light tan it’s going gray .
Lean always your a little lean ..
this way if that full speed plug chop you did over a mile run ..
Won’t drop you in shit .. when some guy comes up your side on the hwy on his custom hobbit or Honda 3 speed with leg shields or that fantic super 6 speed
And gives you the old wank sign and speeds away .. making you look like a right wanker ..
You got to have the confidence that when you hold that baby out .. head on the speedo feet up over the rear turn signals .
Slipping in to his slip stream picking up RPMs closing in for the sling shot over take ..
And it’s 2 miles of flat out .. it will lean off a little ..and as you come up side for the over take .. its locks up .. and you look like a NOB ..it’s not that complicated..
Jet so if your flat out a mile .. and you roll back the throttle just 1/16 it picks up just 1 or 2 mph your just right always be just a little fat on the main .. it don’t hurt running around 40 / mph half throttle to be just a tad fat ..
Sorry if I dragged that out to