Ignition Timing Advance: How to calculate filing the key

[@GeoffSteele]

If you work on the shaft diameter and multiply by pi and then divide the answer by 360 you will get the distance for 1 degree rotation. You can then use this to determine the amount of advance by dividing the amount of metal removal by your answer for 1 degree of rotation.

[@greygrizzlyoutdoors1764]

Thanks alot been asking this everywhere and looking for this with no exact answers. I have a new echo cs 590, had the key taken down 0.14 thousands, went a little more and ended up at a tight 0.22 thousands, so by this video if my crank is similar size I ruffly changed 4 to 4.5 degrees. Wasn't sure if I went to much but you can buy 6 degree timing keys for my saw so I know I did not go to much should be safe thanks alot.

[@johnstonsaw]

Your welcome, glad it was useful to you.

[@jimsworthow531]

give yourself more credit; great job engineering the numbers. I want to ask you- When a person takes material off the key and goes from 26 degrees to say 28 degrees they keep saying they advanced the timing, the person is backing up the flywheel and making it so the magnets on the flywheel pass the coil earlier than before. the point i am making is that they seem to be making the saw fire sooner while the piston is lower in the bore. Isn't this retarding the timing? I understand that ignition is always BTDC. If someone makes the saw fire later than say 26 degrees to 24 degrees the saw is firing with the piston higher in the bore hence that is advancing the timing. I understand ignition and am stuck on this point in terminology.

[@johnstonsaw]

Thank you Sir. You have to look at as going from 24 to 26 degrees your bringing in the spark sooner thus advancing it. When you bring in the spark later say 22 degrees you are retarding it

[@barkerssaws1465]

30k subs in verry little time tell me where you bought them plz

[@johnstonsaw]

I got them with one video that went viral. Really didn't do me much good because those subs don't watch my other content.

[@barkerssaws1465]

@@johnstonsaw that’s what I noticed that there wasn’t many subs that had commented or viewed. Interesting

[@johnstonsaw]

@@barkerssaws1465 probably kids that only watch shorts

[@barkerssaws1465]

@@johnstonsaw your probably right.