Wow, this thread won't seem to die. Since its rolling along I'll toss a post of truth in it and maybe it will be put to bed.
I sat today and actually listened to all this talk about lean saws from someone who actually knew what they were talking about. Yes one of the main guys from Stihl covered fast saws out the box, lean running conditions and new PhaseIII Epa emissions.
From the big horses mouth ALL 2cycle power equipment sold in the USA today is running leaner than ever. This includes all makes. Why, to meet Epa standards. They aren't running leaner than they need to be, only lean enough to pass Epa. This notion these 5100's are leaner than everyone else just isn't true. The exhaust is only allowed to emitt so much pollution and no more. They too are running just lean enough to meet Epa, not a hair more. The assumtion the 5100 isn't surviving as well as the rest might be a true statement but they aren't running any leaner than any other make.
Stihl has raised their rpm levels for most all of thier saws to 14,000 rpms, the 880 being an exception. The motors have been slightly altered with different port timing, carb changes for fuel delivery all in the name of meeting Epa standards.
Stihl has a minus/plus range of 1000 rpms meaning some saws may be hitting well over 14 grand and still be considered witihn the rpm range of the saw.
He went on to say this. If by chance we get a saw out the box that will not idle correctly, will not rev up correctly without richening it don't sell it, return it to them and sell the customer another saw. They do not want anymore limit caps pulled to richen up a saw. The Epa testing is done at WOT, not idle, not during rev up, but WOT. That limit cap is already set at the richest setting the saw can emitt pollution allowed by Epa. To remove it and richen the saw breaks federal law as of 1/1/10. The fine could be as high as $37,500 if caught. This puts the dealer in the clear should the saw fail due to extreme rpms. By law the dealer is no longer allowed to richen up a saw out the box because that saw is already emitting what the Epa will allow. In other words by law its already set as rich as it can be by law.
Now the clincher. As I said before there is a certain amount of what is called acceptable failure. With these new rules in play they know there will be more failures and they understand this. He made clear its much more important now to educate the customer. Dull chains, bad fuel, not knowing how to operate a saw properly is now going to kill more saws than ever before. The older and slower saws would survive these things, the new ones will be more accpetable to failure because of these things. So today the dealers new job is to educate the customer all the ifs and whys to maintaining his fuel, his chains and using some sense when running a saw. The new saws of today aren't nearly as forgiving as the older ones due to new Epa regulations.
So taking in everything he said its obvious they, meaning all makes, are running leaner than ever before because they have to. The makers have no choice in the matter if they want to sell their products in the USA. Me I get a break, no more pulling caps but spending more time to explain how critical the customer knows everything he needs to know about a product that is now very unforgiving compared to days past. I look forward to replacing a few more cylinders and pistons, hell I enjoy it. Just hate the frown I see when they walk in but love that smile when I say don't worry about it, its covered under warranty..