My like-new chainsaw is stalling-out in a very weird way, hoping to know if I should try adjusting Idle or L-adjustment first?

Question

It's stalling-out when idled, it'll let me use it pretty indefinitely it seems. I've got other 2-strokes that bog-down and stall-out when idling (opening the choke a little usually keeps them going, doesn't seem to help my chainsaw though), however my like-new chainsaw (I got it under a month ago brand-new) was stalling-out today after about 20min of moderately-heavy usage, it'd stall-out when idling but would let me rev it & use it, it's just that letting off the throttle fully would begin a ~10sec degradation of engine-power to the point of stalling!

I've seen this in other equipment but my chainsaw was exhibiting something odd alongside this - when I'd go to re-start it, for whatever reason it'd be spinning the chain (w/o me touching the throttle) in idle, quite quickly actually, and stay at that position until I manually touch the throttle, then the second I'd let go of it it would return to the 10sec-til-death routine. I started it, watched the chain go too-fast til I tapped the throttle, then watched it take ~10-13sec to calmly choke-out, maybe 5 times before giving up on it...

Any advice for whether this is more-likely Idle or L adjustment would be greatly appreciated!! The filter isn't clogged at all, there's ample bar&chain oil (and I've got it set to really throw the stuff so it's lubed for sure!), new chain moves smoothly, ethanol free fuel with synthetic oil @sharp 40.0:1 with Stabil added...saw is an off-brand, "scheppach" brand 25cc unit, stated 11k rpm (I've got a tachometer on its way in the mail but nothing here..thing works great and was un-stallable the first ~10x I used it :/ )

Answer 1

So out of the box, brand new, chainsaw manufacturers will set the carbs to run a more "rich" fuel air mixture, this is to allow adequate lubrication during the break in period. after three or so refills, you will need to adjust the carbs and lean them bach out. If you are unsure how this is done i would recommend googling chainsaw carb adjustments,along with completley reading the manufacturers manual that came with the saw as they often have a more specific guide to follow. generally your high jet will need to be turned clockwise by 1/4 to 1/2 of a turn, followed by making a similar adjustment to the LA or idle screw. If you are familiar with the engine noise of chainsaws then your ear should be able to get close. However, if you have a tach,which i recommend, then i would use it along with the manufacturers recommended settings. hope that helps a bit.

Answer 2

When the engine idles to high, then slowly rotate the 'I' screw in counterclockwise direction until the chainsaw runs smoothly. While the engine still runs, adjust the screw labeled 'L.' Slowly rotate the 'L' screw on clockwise until the chainsaw's RPMs drop. Note the screw's position.