Yes I do. Do not over tighten the H and L needles you will ruin the needle seats (clockwise closes the needle jet, counter clockwise opens the needle jet) There is no air mixture needle on a chainsaw carb (2 cycle engine) all are gas mixture needles H - high speed operation, L - low speed operation. [The saw carburetor operates like a 4 barrel carb on a 350 chevy, runs on 2 but kicks in all 4 when you hammer it.] Turn the H needle to 1(one) full turn open (counter clockwise). Turn the L needle to 1 1/4 (one and one quarter) turn open (counter clockwise). NEVER EVER close the H needle to less than 3/4 open or the L needle to less than 1 turn open. If you do you will burn the saw up from lack of oil lubrication. [I have several Jonsereds saws a 52E, 451EV, 49SP, 520SP, 621 race saw, 630, 70E, 70E race saw, 80E and last but not least a 90E. I worked many years for the importer and distributor of Jonsereds as a Territorial Rep. All my saws run like a top. My newest saw is a 1984. I chainsaw carve and cut firewood with all of them year round. In short I like-em, they're the best.] I find that all my saws run the best and strongest with the carb set at around 7/8 turn open on the H needle and just above 1 turn open on the L needle. The idle screw I set last after the saw responds correctly to the carb settings. I quick throttle the saw to make sure the saw picks up RPM and doesn't fade out, put in a log to make sure it maintain tourque under load and not bogg down (tweak the H & L if needed, remembering the 7/8 - 1 1/4 rule I adjust the idle screw to where the saw sound smooth and un-labored at idle. I never let it idle to where the chain moves when it idles. For safety reasons. Hope this helps. EdN
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