One ring vs Two rings on 2 stroke chainsaws

[brinkwolf]

Ok, I have seen it said many times on here about Husky saws having only one ring on their pistons. Alot of you Stihl fans use this as your main argument when the question of Husky saws not lasting as long as Stihl saws. My feeling is that first off it is a 2 stroke engine(oil is mixed in the fuel so second ring is not actually needed) and second what good is multiple rings if one fails anyway. I have seen in my line of work on all sorts of engines what happens when just one of the two or three rings on a piston fails, the piston and cylinder are scored (I had a 2 stroke multiple ring piston boat motor do this). So let's here your thoughts on the subject.............

 

[stihlboy]

Ok, I have seen it said many times on here about Husky saws having only one ring on their pistons. Alot of you Stihl fans use this as your main argument when the question of Husky saws not lasting as long as Stihl saws. My feeling is that first off it is a 2 stroke engine(oil is mixed in the fuel so second ring is not actually needed) and second what good is multiple rings if one fails anyway. I have seen in my line of work on all sorts of engines what happens when just one of the two or three rings on a piston fails, the piston and cylinder are scored (I had a 2 stroke multiple ring piston boat motor do this). So let's here your thoughts on the subject.............

two is better IMO because it helps minimize cylinder leakdown

 

[MtnHermit]

Two rings would have double the friction, all else being equal.

How does Husky create the ring joint? Simple butt, slanted overlap, stepped overlap?

 

[brinkwolf]

two is better IMO because it helps minimize cylinder leakdown

Ok now for rebutle, If it's built right you wont get leak down(still alot of one ring husky's out there holding high PSI'S). Next......................................

 

[FELLNORTH]

two is better IMO because it helps minimize cylinder leakdown

THATS NICE AND EVERYTHING, BUT... DOES THAT AMOUNT LESS LEAK DOWN ADD ENOUGH POWER TO OVERCOME THE FRICTION CREATED BY HAVING TWO RINGS

 

[brinkwolf]

Two rings would have double the friction, all else being equal.

How does Husky create the ring joint? Simple butt, slanted overlap, stepped overlap?

Couldn't tell you myself you have to ask them. I just know they work.

 

[pa.hunter]

piston

is nothing but a bearing in sence for ring , more friction, more heat ,more wear , if it was a tapered ring it would make differance because as tapered rings wear top ring takes the blunt of compression when it gets to be flat across sealing serface second ring comes into play keeps it from leaking or bypassing and with 2 rings you may have little more compression till it gets warm just my thoughts nothing set in stone

 

[Evan]

doesnt matter.

i come from the motorcycle world. worked on alot of 2 stroke motocros bikes. most all the 125cc kawasaki yamaha suzuki honda are 1 ring, the jump to 250cc brings the additional ring, maybe its needed there.

i have never felt one ring was aproblem, especialy on stuff smaller than 125cc. the added ring almost seems like it would be exstra drag, heat, and wieght in the cylinder. and yeah most the time when piston or ring goes so does the cylinder. so whys it matter if the one ring is good. usualy it isnt cause they get smeared together.

but i guess these are motorcycles, not little chain saws. though they do both run in same rpm range.

i was suprised to see 2 rings on any saws.

 

[brinkwolf]

Well I'm not pro Husky or Pro Stihl. I thought I would just start this thread to get everyones ideas on the subject since it always seems to come up when the two are compared.

 

[brinkwolf]

doesnt matter.

i come from the motorcycle world. worked on alot of 2 stroke motocros bikes. most all the 125cc kawasaki yamaha suzuki honda are 1 ring, the jump to 250cc brings the additional ring, maybe its needed there.

i have never felt one ring was aproblem, especialy on stuff smaller than 125cc. the added ring almost seems like it would be exstra drag, heat, and wieght in the cylinder. and yeah most the time when piston or ring goes so does the cylinder. so whys it matter if the one ring is good. usualy it isnt cause they get smeared together.

but i guess these are motorcycles, not little chain saws. though they do both run in same rpm range.

i was suprised to see 2 rings on any saws.

I would have to agree here.....................................

 

[J.W Younger]

2 rings may make the piston a little more stable in the bore

 

[brinkwolf]

is nothing but a bearing in sence for ring , more friction, more heat ,more wear , if it was a tapered ring it would make differance because as tapered rings wear top ring takes the blunt of compression when it gets to be flat across sealing serface second ring comes into play keeps it from leaking or bypassing and with 2 rings you may have little more compression till it gets warm just my thoughts nothing set in stone

Ok, there is no real compresion ring on a 2 stroke like on a 4 stroke. The compresion ring on the 4 stroke(like your car or truck motor)is the wavey looking ring at the top. All other rings on this piston are for wiping purposes and keeping the piston straight to the bore.

Ok sorry I didn't read this well, I'm at work.

 

[brinkwolf]

2 rings may make the piston a little more stable in the bore

Only real purpose I can see for the extra ring. But if one is correct and the bore straight than one will work.

 

[Evan]

i agree might keep piston rock to a minumum on larger bores

 

[brinkwolf]

Ok come on all you Stihl experts let's here your side of this.

 

[HolmenTree]

My older brother raced a Jonsered 80 in the 1970s and one of his mods was pulling out the bottom ring and running only one. That 80 was fast. Much more rpm and power. In the woods it would definately wear out twice as fast but then he only ran it for competition.

 

[04ultra]

My 3120xp is single ring .......LOL...NOT!!!


anybody care to mention 372xp
.

 

[04ultra]

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 ........

 

[brinkwolf]

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 ........

Yes, but then why?????? Like said before maybe it's because it stabilizes better in the larger bores. But why does Stihl put them in their smaller saws.

 

[Banshee]

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 ........

I think and someone will have to verify that Husky also make 1 ring conversions. My 372xp is 1 ring. It was rebuilt at a Husky dealer this way.