One ring vs Two rings on 2 stroke chainsaws

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I didn't really read the thread, but my wife got one ring. If I ever get rid of her, no woman is ever getting a ring from me, so I guess one ring is better?

I think the same tradeoffs occur. When my fiancee got the second ring, friction went up, performance went down, and things got cooler. I expect the relationship will last longer than it would have with just the one ring...but the rpms have been reduced.
 
I think the same tradeoffs occur. When my fiancee got the second ring, friction went up, performance went down, and things got cooler. I expect the relationship will last longer than it would have with just the one ring...but the rpms have been reduced.

If your young than just wait. About the time your cylinder starts to wear down she will get ramped up again(something about women getting thornier the older they get). Then she will be on the lookout for a new saw......:censored:

:greenchainsaw:
 
I think the same tradeoffs occur. When my fiancee got the second ring, friction went up, performance went down, and things got cooler. I expect the relationship will last longer than it would have with just the one ring...but the rpms have been reduced.


Excellent post of the day.
 
If your young than just wait. About the time your cylinder starts to wear down she will get ramped up again(something about women getting thornier the older they get). Then she will be on the lookout for a new saw......:censored:

:greenchainsaw:

Unforunately I'm getting old...and not responding to modification either!
 
Huh, Andy have you ever been to a motocross race? You want to talk about Screaming 2 stroke engines. And who said anything about a low rpm trail bike.

And so if the first ring in a two ring set-up fails first, then it doesn't matter how many rings you have. Were is the pieces of that failed ring going to go? Sounds like a scored piston and cylinder to me.

The motorcross bikes I've had were rebuilt about every three races or so. It was even suggested in the manuals that the be done every 8-10 hours of operation under normal use.
 
one ring/two ring

Keep in mind that pistons historically had many rings. As time passed, the trend was to fewer rings. Having two rings versus one ring may--sometimes--reflect nothing more than the date at which the basic engine design was first laid down,or the individual preference of the engineer in charge. Far more important, in my fallible view, is the basic quality of materials, design, and workmanship of the engine. We can't easily examine the microstructure of the steel or cast iron used in piston rings. The amount of precision is also hard to know. Cylinder accuracy is still another variable and so is its quality of cooling. Bigger, better fans, ducting, etc. If a brand you want has a decent engine power and reliability reputation, the number of rings should not considered a major factor.
 
As time passed, the trend was to fewer rings.

Also as time has past engines are producing horsepower at higher and higher RPM. The lower the RPM to achieve a given HP the larger the bore or longer the stroke needs to be and the longer the period of time the rings are exposed to cylinder pressure. All these contribute to increased blow-by and drive the need for additional sealing. On the other hand run an engine up over 8-10k and it hardly needs a ring at all, sealing can be achieved with piston fit and lube alone. Many small model engines have no rings at all.
 
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372 x 2

385 x 2

390 x 2

395 x 2

3120 x 2

must be a reason the big modern huskys run 2 rings ........

the husky 371xp had one ring, i saw it on a service training video from 1995. I was told from my husky dealer the older 372xp's had one as well, back before some kind of epa thing that resulted in husky going to the two ring in the 372xp.
 
Fat rings are good in some ways like wear and heat transfer but they are hefty and don't like high RPM. Even a 1.5mm ring is a problem if you want to make a high RPM saw.

TW, how much could a 1.5mm ring weigh? Even if it was heavy couldn't it be offset 3X by lightening the piston windows? This is all just stupid theory in the real cutting world. Two rings, one ring, who cares? It's the operator, technique and how he files and sets his saw up. That does the talking as does simple tangible mods,not armchair conjecture designed to confuse those who know otherwise or those who are willing to listen because they don't know any better.
Working in the field offers far more illumination that working with a calculator or in the lab.
Gypo
 
TW, how much could a 1.5mm ring weigh? Even if it was heavy couldn't it be offset 3X by lightening the piston windows? This is all just stupid theory in the real cutting world. Two rings, one ring, who cares? It's the operator, technique and how he files and sets his saw up. That does the talking as does simple tangible mods,not armchair conjecture designed to confuse those who know otherwise or those who are willing to listen because they don't know any better.
Working in the field offers far more illumination that working with a calculator or in the lab.
Gypo

Different applications Gypo. The problem Timberwolf is addressing isn't about reciprocating mass, but rather that ring mass can put a ceiling on max rpms, because heavier rings will flutter, damaging the ring, groove, and allowing blowby.

I would bet that a race saw builder can build a much better work saw than the race saw that an every day faller could build.
 
TW, how much could a 1.5mm ring weigh? Even if it was heavy couldn't it be offset 3X by lightening the piston windows? This is all just stupid theory in the real cutting world. Two rings, one ring, who cares? It's the operator, technique and how he files and sets his saw up. That does the talking as does simple tangible mods,not armchair conjecture designed to confuse those who know otherwise or those who are willing to listen because they don't know any better.
Working in the field offers far more illumination that working with a calculator or in the lab.
Gypo
You were quite the Arsehole back in those days! Lol
 
Two rings makes twice the friction and twice the wear- than one ring does.
 
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