Tldr
Tuned pig fat on the very first cut. Next time it will have a better chain. Stock 325 loop of semi chisel on it. Tuned it better on tank two and three. It pulls hard in that dead dry ash. Cut a bunch of black locust on the third tank about 22" and it was coming around nicely. Nextweek maybe it has a chisel loop on it of something a bit more aggressive. Oh, btw it's base cut 60 and the band is 13° now on the chamber. The piston is near 11° in that area. You see the 0.090 margin there on the piston? That is the quench area about 20% of total bore area. It has a nice billet muffler outlet that came in with it. The muffler exit port is 80% of the piston window area at the exhaust port.
Wrist pin clips in these are questionable imho. This one has new OEM Stihl clips in it now. The piston pin bore had some serious issues and the wrist pin had to be beaten out. The one clip was jammed in a bur in the clip area. Even with the burs gone the wrist pin was seized good on both sides. We figured the plating from the piston coatings got in there. It was honed till it floats nicely as it should. Three bottom corners of the piston skirt had razors edges removed, not good. One ring in it for now. These aren't anything but cheapo cast iron jobs from the factory. It might be getting Stihl, Caber or another quality brand if the OEM becomes a problem down the road. This saw is local so it will be messed with again especially the air filter. It's passing fines with a felt filter. This dry wood could kill it with the mesh filter installed, I'm sure.
The owner is tickled pink.
He is also very very happy with his 600SX that runs a 28" b&c. That is ported with a nice foam filter in it. That saw is impressive for 59ccs. And no it has no machine work and it is near stock compression basically. The base was cut just enough to true it up. The quench is not touched and it's only out 0.002 now. It does have a 0.004 base gasket, dual port muffler, and nothing else. Stock carb, tiny thing there, and the stock inlet area just cleared out some. It needs a bigger carburetor imo.
The 7310 there is just a muffler mod and a tiny timing bump. It needs more later. It wanted nothing to do with 8° igntion advance or even 6°, oddball.
^ Same deal for the 492 as the 7310 ^
An almost new CS501 is sitting there waiting to be sold or ported and sold. It only had a few tanks through it but no heated handles
The man wants heated handles on everything now. Building him a ported custom artic 660 next from one of my none artic 660s I've had for years. Two more left after that and they are going full monty then sold. He needs to fill the gap between the 1200 and the 7310. The 1201 is still on the bench NOS complete bought new as parts. It's getting done up eventually.
These little Echos and Shindiawa saws are fun to do but require some time to figure out in the first one of each model and cylinder type. This carburetor was way too small. It has been opened quite a bit now. Ported entry, ported venturi, thinned shafts, knifed butterflies and tapered out the back to meet the boot ring 17mm there. Doing the 501 was a challenge to stay within the exhaust casting area. Exhaust is 103° now but could be 99°. Getting that port to wrap around was different. The cylinder was out of square on the skirt 0.004 and 0.003 on the base. Surprisingly the quench area was straight, short and flat but 0.068 out there, way out there! Now it comes in at 0.022 to 0.028 as it rises. Yes this does help mix A/F. It also helps the transfer direction by not cutting the piston down. Stock piston here with no freeport. Could still be widened more on the intake and exhaust ports. I left 0.050 on each skirt side for a smooth ride possibly more in one area.
After having every stock new saw out of square at the base none are right from the factory not even Stihl. 0.002, okay, 0.006 or more, not so much. An old 394 I got was out 0.005 or 6 cut at a west coast shop probably twenty years ago. None the less it was off by a good bit and you can see it in the piston wear patterns.
Having an angled squish band and the cylinder on straight is priceless
