Hello everyone, I'm new to this forum and this is my first post so please bare with me if you find it a bit stupid. The short version of the question is this: Can I put a bar larger than spec on a chainsaw (say 25+ inch on a Stihl MS291) if I am only going to cut wood under the spec size (less than 20'' in this case)? To put it differently, is the maximum bar size only a function of the engine power (and thus maximum energy transferred to the wood), or are there other factors at play? Here is why I am asking: I'm about to upgrade from my tiny 181C to an MS291 (I can't really justify more money) and in addition to using it as a normal chainsaw, I would like to use it for some milling (with an Alaskan mill). The problem is that these mills waste several inches on either end of the bar, so if I stick to the maximum recommended bar of 20", then I limit myself to much smaller logs, but if I get a bar closer to 25" then I will be able to cut 20" logs.
Hmmm. I guess in theory it shouldn’t be an issue. Its still pulling extra weight though... If your considering a new 291 you may also want to consider some used alternates that are a little larger and would do the milking and firewood without issue.
Yes, that’s it in a nutshell. You’re also asking a little bit more of your saw than crosscutting. You could probably be fine with a 20” but I think you will find yourself wanting some more power for most logs. If you’re on a budget I’d also recommend looking for something used with a little more power. At least 70cc, preferably 90. There’s some knowledgeable folks around here who could probably steer you towards some good options. Welcome to the club!
The recommended max bar length also is determined by the oiler. I don't think you'll be very satisfied milling with a sub 60cc saw. I'd go 70cc minimum for milling 12" boards. Another consideration is the saw's construction. The 291 may be a plastic cased saw, also. If that's the case, milling may be too hot for it
I personally wouldn’t mill with the 291. They’re decent firewood/“ranch” saws, but would struggle milling. A used big saw is usually the way to go for your plan. Get the 291 only for normal cutting duties.
