Just wanted to throw this out there....

Today I was cutting some hackberry with my Makita 6401BB And broke the Left Rear AV spring. I really didnt want to put the saw up and get a smaller one so I pulled the recoil cover to see how the spring mounted and if I could tighten or fix what happened. The spring broke right in the middle so it is done. To get to it you pull that big black plug out with the large hex key, and take the torx bolt out from down in the center of the spring to remove the spring. The Large hole left looks about as wide and deep as the large rubber AV isolators that are on the larger Stihls. You can bolt one of those down in place of the original spring. Save the black plug for when you get the right spring in the mail. The Stihl part fits in the hole perfect and its the right length. I cut with it and to be honest it feels better than the original (worn out) spring felt. It should be a good temp fix till the correct part comes in the mail. Just figured I would put this on here in case anyone broke a spring and had a parts only stihl laying around.