New Stihl MS 280-I

[cmonSTART]

I'm curious whether any of the experienced saw guys in there, or anyone else for that matter have run across one. Stihl is trying something new out on the MS 280 - electronic high end mixture adjustment. In place of the high speed needle, there is a little fuel solenoid wired in parallel to the kill circuit. In the ignition module, there is a little microprocessor which monitors how well the engine is running based on RPM. About 30 times a second, this solenoid opens and closes, thereby metering the fuel in the carb. The processor monitors how the engine responds to tests (temporarily cutting off the fuel for a tenth of a second) and adjusts the mixture accordingly. Supposedly, it can compensate for changes in altitude, temperature, barometric pressure, and even poor gas they say. It sounds great on paper but I would like to see how these units hold up over time.

I ran the unit and cut some wood with it as a test. It started easily and seemed to run OK. The high end mixture sounded pretty good, close to where I set them (which is richer than out of the box). It seemed a little slow to return to idle, but not like an air leak. I will be really curious to see if these start coming in within a couple years with burned up pistons, and how well the modules and electrical bits stand up.

Anyone ever see one?

 

[bertcarrier]

I just talked with a guy up here in MI, who said he cuts 50 cord per year, selling it in the newspaper. He said that it is the best saw he has ever owned, and he has had them all. I believe him, too. I have a tree service, and I run both Husky and Stihl. I can't wait to try this, because top-end (high speed) adjustment is everything on a saw. Just curious, why do you set them slightly rich? for longevity?

 

[computeruser]

Welcome to the world of technology! Husqvarna also has some of their 575s set up this way (limited number...might only be test machines?).

I haven't put any time in on one of these yet, but the guys who have used them thought that they were pleasant enough to run and that the fuel metering technology helped create a nice broad torque curve, somewhat wider than the standard 280. It seems like an interesting idea, especially for the tuning-impaired saw owner. I'll try to get a bit of demo time on one next time I'm at the shop to form a true, personal opinion.

That said, my two cents: it's one more thing to break, and I'd rather not be the beta-tester. At least a three-screw carb can be field-fixed fairly easily. The existing carb designs out there do not come up short on performance, reliability, or durability. They only come up short on emissions, which in the great scheme of things I couldn't care less about. Put a couple exhaust scrubbers on the local coal-fired power plant and leave our 2-stroke machines alone, thank you much.

 

[cmonSTART]

That's about my sentiment, computeruser. The sad thing is, at least at this end of the industry, the dealers and more so the end owner/user are the beta tester.