Some pretty useful info here for Stihl chain identification although for some reason I don't see anything listed for the 500i. Look at the PDF attachment for full details but here's the text version of the overview. Pitch 1 = 1/4" 2 = .325" 3 = 3/8" 4 = .404" 6 = STIHL PICCO™ (3/8" Extended) Gauge (on drive link) 1 = .043" (1.1 mm) 3 = .050" (1.3 mm) 5 = .058" (1.5 mm) 6 = .063" (1.6 mm) 0 = .080" (2.0 mm) (0 = Harvester Chain Only) Cutter Type P = STIHL PICCO™ R = STIHL RAPID™ Cutter Shape C = Comfort (Low-Vibration Version) D = Duro (Carbide Tip) DS= Duro Special (Carbide Tip) M = Micro™ R = Rescue (RDR chain, especially designed for MS 460 R STIHL Magnum™ Rescue) S = Super (Chisel) Special 3 = Single-Humped Drive Link F = Full Skip H = Semi Skip (Half-Skip) or Harvester (i.e. on .404" RMH) K = Classic Cutter design L = Square Ground S = Special
I also think this is good info. Maybe it should be a tacked/permanent thread or in a resource, knowledge body. I learned a little bit from it.
This is how I have been figuring out what chain I need for any given saw. I run the RS on everything I can. Tried other chains but keep coming back to Stihl. They seem to hold up really well,they might be a couple bucks more than some others, but it works for me. Pretty simple chart to figure out what you need.
Because the document has been updated. It’s listed with the 661 family. https://www.stihlusa.com/WebContent.../STIHL-Saw-Chain-Selection-Identification.pdf
