Ignition timing

[Nc grease monkey]

Using a snap on variable advance timing light I am getting advance readings of about 55 degrees on a ms 362cm, when first crank it it's around 20 then tap the throttle and it jumps up to 55. Checked my ms441 and it's over 45 degrees advanced. Thoughts?

 

[srcarr52]

That's a 4 stroke light, for something that fires every other revolution. Divide the number by 2 for the true timing advance.