Chainsaw Repair

Most saws are timed at 26 to 28 advance .Some of the older lower compression at up to 35 which if that were done on a high comp saw all you'd get is a sore arm because you'd never get it started .

I've never done much on the Stihls but I have to some extent with  a few Macs .At about 30 advance is just about the limit of getting them started without pulling your arm out of the joint .

You could figure out by using the circumferance of the flywheel and checking by filing a little at  a time off the key how much you are advancing it .If it doesn't work put a new key back in the slot .