What limits older saws to be relatively slow?

[ilikeurtractor]

This should have an obvious answer but after searching I can't really find anything on it. Why are older (pre-80's usually) saws so slow, at least the larger displacement ones (>70 cc)? What is limiting their speed? Is it carburetor design that inherently limited air flow? Points start "floating" at higher speeds (?) I know some saws like the McCulloch Super 44A and some of the Stihl saws had methods of limiting speed like activating the choke or restricting the throttle but I don't see that on all saws. I read where the McCulloch BP-1 had some sort of governor because it could potentially over-speed and cause problems and this is claimed to happen because of its exceptional balance but newer saws can outrev the BP-1 (I would think) and they don't have balanced pistons. I'm not necessarily looking to speed up old saws as I realize they weren't designed to go faster than they do, but I'm puzzled as to what is holding them back.

 

[beavis331]

Your main limiting factor is going to be port design. They were designed for torque not rpm.

 

[Stihlbillie]

^correct

 

[SEAM]

Many of the modern saws sound awfully fast as they rev very high without load. When put in wood the rpms will drop some. I let a friend of mine (trigger-happy Husqvarna fanatic) use my Stihl 034 Super and an old McCulloch CP80 and he was impressed with the cutting speed.

 

[alexcagle]

Same thing that probably limits older people's speed.
Don't breathe well, let alot of gas out the back end, are heavier, clogged up, and generally just worn out.

 

[Big_Wood]

there are alot of fast older saws. you must be talking about the old stihls

 

[alexcagle]

Good one!

 

[Big_Wood]

View attachment 505738 View attachment 505739 Good one!

even a die hard stihl guy should be able to see the 041-090 saws are slow turds. reliable as can be but turds no less

 

[alexcagle]

No lie eh. I'll drink to that.

 

[alexcagle]

ahhhhhh! Husqvarna Orange ! 041, 051 saws were mid 60's designs that were introduced in 1967-68.
The 090, was if I am correct, at heart, a Contra Lightning designed In the mid-50's and produced about 1958.
What was Husqvarna or any other chainsaw manufacturer producing around the same era, that wasn't a lower reving turd? ;-)

 

[Little Al]

Just because some older saws don't rev out a wail like a banshee doesn't mean they do not perform in the cutting department as said toque not revs grunt produced at lower speed/revssome of the bigger vintage machines will give the modern jockeys a run for their money as they can pull a larger size chain.

 

[Big_Wood]

The 041, 051 saws were mid 60's designs that were introduced in 1967-68.
The 090, was if I am correct, at heart, a Contra Lightning designed In the mid-50's and produced about 1958.
What was Husqvarna or any other chainsaw manufacturer producing around the same era, that wasn't a lower reving turd?
View attachment 505767 (Not me, BTW) ;-)

Even getting into ones like the 076. What a heavy turd of a saw. The 2100 was a good saw but I would have rather run an 084. Then the 066 came out and finished the 2100 off. Then of course husky came out with the 394 and wrote stihl clean off. In modern times there are good saws from all manufacturers. I just hope not all of them go down the direction stihl sent the 660.

 

[alexcagle]

...Encore une fois, je vais boire à celui, Aye.

 

[svk]

The older low revving saws aren't going to limb as well as say a 550XP but on larger wood they cut just fine and have been getting the job done for years.

 

[alexcagle]

Even getting into ones like the 076. What a heavy turd of a saw. The 2100 was a good saw but I would have rather run an 084. Then the 066 came out and finished the 2100 off. Then of course husky came out with the 394 and wrote stihl clean off. In modern times there are good saws from all manufacturers. I just hope not all of them go down the direction stihl sent the 660.

Sorry Shane,
That turd pic was a little too real looking on a hung over Tuesday for Me. I omitted It out of respect for others gag reflex.....Lmao

 

[JonCraig]

I'm guessing (and it's just that--a guess), that it's a combination of longer stroke, which makes for high torque but lower rpm, and lots of mass, which does the same. Thinking of a 350 vs a Honda 4-banger. Limited analogy, granted.