You are right, Woody. We all develop tunnel-vision sometimes, assuming all are in a situation similar to our own. I flat out don't cut any softwood. In fact, more than 80% of what I cut is oak, but I admit I've never heard of "Gerry oak".
It's "Garry Oak", also known as "Oregon White Oak" (although it's native range is from California to British Columbia). It tops most North American charts in terms of hardness. You can learn more about it here:
http://www.zenaforest.com/blog1/2014/1/7/what-is-so-special-about-oregon-white-oak-part-3
I just looked up Pacific Madrone (never seen it, myself), and it does indeed fall between white oak and red oak. This makes me wonder what you mean by "cuts just fine", as I have spent more hours in the last five years (I cut more than 20 cords per year) than any firewood cutter I know, and I've never seen a saw under 70cc pull a 20" bar "just fine" in oak. Of course, some also think 4-cylinder cars accelerate "just fine", but I'm not among them.
That's funny, I own a Mazda CX-5 with a naturally aspirated 4 cylinder engine and I think it accelerates just fine. It's a rare traffic pattern that I can ever floor it. It's faster than the muscle cars of the 1960's in a 0-60 test. But in my mind, all cars (excepting exotics) are slow because I ride three different 1 litre class Ducati motorcycles. But the Mazda is a reliable and capable performer for everyday driving so I don't get carried away wishing I had something even faster. It wouldn't get me there any quicker and I have the motorbikes when I want to pass everything in my way and be the fastest thing on the road.
When you say, "makes me wonder what you mean by "cuts just fine"", I mean it goes right through a 20" round of Madrone. If I had a 80cc saw in my truck parked 30 yards away, yes, it would make each cut slightly faster, but I wouldn't walk over to get another saw because that would take more time and energy than just making the cuts with the saw in my hand. If felling a large tree or bucking a lot of hardwood or softwood much bigger than 20", yes, I would grab the more powerful saw. But the well optimized smaller saw will go right through it with light pressure. It would take a lot of cuts in big hardwood to make me want to grab a bigger saw. That's what I mean when I say "cuts just fine".
The Stihl 026 was rated 2.6 kW, the MS 261 is rated 3.0 kW, so yes... the 261 is a more capable saw. However, I find 20" marginal on even my 3.3 kW Stihl 036, when I have it buried nose-deep in red oak. It cuts fine when the wood is small enough to keep the nose out of the wood, but then one could say you'd be fine with a smaller bar, too.
It looks like your 70cc saw is only rated 10% more HP than the 261 C-M. Did you know that there are a lot of things that could cause your saw to produce 10% less power or consume (waste) 10% more power than if everything was optimal? I've found by optimizing for efficiency allows a smaller saw to pull a bigger bar without straining. Things like chains without extra anti-kickback components dragging in the cut help quite a bit in bigger wood (even if not so much in smaller wood). Plenty of bar oil that's not too thick (use winter oil on cooler days), proper chain tension, fuel mix, carb adjustment, etc. etc. etc. By far the biggest one is a chain that is very sharp and cuts absolutely true. A lot of people unconsciously file their chains slightly unevenly L/R. While this is inconsequential on smaller cuts it can easily rob you of 10-20% of your total power in a big cut. I've found I can make big chips at high rpm's with a 50cc saw in 20" hardwood. Would a saw with 10% more HP cut even faster? Of course, everything else being equal, but it wouldn't quite be 10% faster.
This is where you leave the rails, Woody. You do custom grinds for different wood species? Honestly, you must have too much time on your hands. I'm assuming most people aren't swapping chains for each type of wood they're sawing, and that most are using a factory grind on a Stihl 33-RS or 33-RSC chain, with their 50 or 60 cc saws.
The factory grind only lasts until you sharpen it the first time. And I've never had a chain that cut faster new (at least not in the last 15 or 20 years) than it did after a light hand file. You admit above that you only cut hardwoods. I cut both. The factory chain is setup for hardwoods in terms of the height of the depth gages. Stihl recommends lowering the depth gauges for softwoods for faster cutting. Maybe Stihl has left the rails? A blade matched to the task at hand? Loony! LOL! In reality, I've found softwoods cut faster with the gauges filed further than spec. And most hardwood (Garry oak can be the exception around here) cut fastest with the softwood depth on the gauges.
The thing is, there is no problem going from hardwood to softwood with the depth gauges suitable for hardwoods (although you will be cutting about 20% more slowly than optimum) but not vice versa. So, if you primarily cut hardwoods, just use those chains for everything. But if you primarily cut softwoods, it makes sense to have a special chain for extra hard wood. Since I rotate a number of chains to insure I always have a suitable one ready to go, I also keep a sharp chain handy for serious hardwood duty. Yes, if I'm going to be cutting any serious amount of Madrone, Garry Oak or even Maple, I'll put on a sharp chain that cuts hardwood well. I'll sometimes use this (hardwood) chain if I'm going to be doing a bunch of windfall, scrappy wood, small limbs etc. because it's not as likely to grab and pull the small stuff around - it's smoother and I'll never miss the faster cutting speed as I would if I were making lots of rounds out of big Douglas Fir or even mature Alder. Big green Alder cuts more like a softwood and can benefit greatly from lowered depth gauges (commonly called "rakers").
On the subject, though, I usually take the depth gauges down about 20% below factory grind when it comes time to sharpen my 33-RS chains. Yes, this does require more HP per inch of bar, but it cuts oh-so-much faster when you have the displacement to back it up. However, my original comment about 20" being a lot of bar on a modern 50 cc saw were applicable to the factory grind, which is how I use each of my chains prior to first sharpening. Also, I do that on every chain I sharpen, I don't segregate them by what species I'm cutting.
Nobody segregates chains by species! The idea is to have a couple different grinds so you always have a suitable cutter for a wide variety of likely conditions.
I assume 99.99% of chainsaw owners use the same chain all day long, and aren't out there swapping chains for each tree they approach.
People don't swap chains for each tree they approach but they definitely put different chains on for different tasks. It only takes 2 minutes to swap to a fresh chain.
Personal attack? What about the aforementioned factory sharpening?
I think you're a little sensitive here because I don't see the personal attack. When I say people might be lacking in chain sharpening skills, I'm not pointing at you, I'm saying that might be a reason why a 20" bar might overwhelm a 50cc saw. Another reason might be low compression, misadjusted carb, bent or worn bar, new tight bar, engine not broken in, etc. There are a lot of reasons why a 20" bar could overwhelm a 50cc saw (or a 70cc saw for that matter). And it's so commonly stated as fact that a 20" bar is too big for a 50cc saw, I'm assuming a number of factors are at play. So don't take it personally.
The fact that a 20" bar works well for me, even in the 10% of wood I cut that's truly hard, tells me that those who claim it's silly haven't optimized their setup. I run a 18" bar about 75% of the time but that's mostly for it's easier handling in tight spaces when there is no benefit to the 20" bar. In reality, I generally have to read the bar marking to know which bar I have on there.
There is no doubt that more cc's can compensate for a lot of small issues. I've found a smaller engine makes me more sensitive to my equipment and how I'm using it. There is no doubt that a bigger saw could save me a couple of minutes here and there on more demanding tasks but the time thing is really minimal and doesn't amount to a hill of beans in the big picture.
