One ring vs two

[Marshy]

Like you said randy,the piss must be revved out of these saws.

Does the piss come out easier when its cold?

 

[petedaycab]

Do single ring setups last as long as a dual ring setup? My 024 ran 25+yrs. before I went through it, and it went through a bunch of wood.

 

[David Young]

I've never had to travel to work..waiting for the Ibew Union office to open up now.

What local brother? I'm 300

 

[jmssaws]

Do single ring setups last as long as a dual ring setup? My 024 ran 25+yrs. before I went through it, and it went through a bunch of wood.

I've thought about it and I don't know,once again there are so many variables for how long one will last I don't know how anybody could say from my point of view. In theory 2 should but dose the stress relieved from running one out weigh the durability of two. I'm fascinated fellas. Teach me something.

 

[jmssaws]

Does the piss come out easier when its cold?

It doesn't seem that way.

 

[David Young]

Jason.
A little bag lapping if I may.

I appreciate how you prove ideas for yourself scientifically. You don't seem to just take others ideas for truth. You see if it works for you.

Keep up the good work.

 

[Deets066]

Would removing one ring be easier on crank bearings? Possibly, or it could be harder on them because of stability issues.

 

[Deets066]

Jason.
A little bag lapping if I may.

I appreciate how you prove ideas for yourself scientifically. You don't seem to just take others ideas for truth. You see if it works for you.

Keep up the good work.

He's already a horn tooter, you ain't helpin!

 

[Frank bierce]

What local brother? I'm 300

Local 932...Oregon coast. Signing at
Local 112 book 2 at the moment.

 

[Definitive Dave]

I need to purchase stock in the company that makes this rope for stihl,maybe recoup some money.

I have four rolls of the 4.5mm with broken spool centers that I wont sell like this if you want one, let me know.
Dave
also rescue handles from Stihl (larger and rounder, meant for use in firefighting gloves, too big for some hands) and Oregon (smaller diameter grip but more angular and less roundy)

pull starting with the Stihl D and a short rope on the drf255 044 that was flooded I pulled flesh off my palm in two places and got a pair of bruises

 

[Keith Gandy]

From a 2 stroke article: When you have less heat transfer with a single ring, the ring gets over-loaded and ring seal fades and with fading you get combustion blow-by... With blow-by you get power LOSS.. So, if you have blow-by (which you do) and you Lose power (which happens with blow-by) then you will now be over-fueling the cylinder, contaminating the intake charge (due the blow-by) which, in turn, lowers charge purity, which in turn, lowers power... So, now you have made your engine make less power BUT you are still feeding it with the same fuel (via carb jets) for the stock power.. So, now you have created a over-fueling (rich) condition inside the engine.. Rich conditions COOL the piston which is needed because of the ring over-load, and this same rich condition also aids in the power LOSS.. you can not make power with an overly rich condition... So, it is a cycle that repeats over and over.. ring over-loads, charge density lessens, rich conditions occurs, power ouput is dimished, piston cools, ring seals normal again, back to stock power (or close to it) rinse, wash, and repeat..It is VERY hard to seize an engine with a very rich condition... This is a very good reason for BRP to use a single ring. Less engine failure due to over-fueling.

 

[jmssaws]

Videos are loading. I'm kinda baffled at how Kool these saws run. I would have guessed a couple hundred degrees higher.

 

[Deets066]

From a 2 stroke article: When you have less heat transfer with a single ring, the ring gets over-loaded and ring seal fades and with fading you get combustion blow-by... With blow-by you get power LOSS.. So, if you have blow-by (which you do) and you Lose power (which happens with blow-by) then you will now be over-fueling the cylinder, contaminating the intake charge (due the blow-by) which, in turn, lowers charge purity, which in turn, lowers power... So, now you have made your engine make less power BUT you are still feeding it with the same fuel (via carb jets) for the stock power.. So, now you have created a over-fueling (rich) condition inside the engine.. Rich conditions COOL the piston which is needed because of the ring over-load, and this same rich condition also aids in the power LOSS.. you can not make power with an overly rich condition... So, it is a cycle that repeats over and over.. ring over-loads, charge density lessens, rich conditions occurs, power ouput is dimished, piston cools, ring seals normal again, back to stock power (or close to it) rinse, wash, and repeat..It is VERY hard to seize an engine with a very rich condition... This is a very good reason for BRP to use a single ring. Less engine failure due to over-fueling.

You don't have to yell

 

[jmssaws]

I used the same bar and chain with 8pins on both, both are tuned at 14000 both have the same type muffler and bored carb,both have 030 of the key and the same gas and oil,both are right around 230lb of compression, yadda yadda and so on. I tried to run them the same and after a warm up cut they both were 210 degrees.

 

[jmssaws]

Also I can't really say I was loading these saws,I'm sure in warmer weather with a big bar and a long cut temps would be much higher but I believe the science is still good.

 

[jmssaws]

 

[jmssaws]

 

[Jughead]

From a 2 stroke article: When you have less heat transfer with a single ring, the ring gets over-loaded and ring seal fades and with fading you get combustion blow-by... With blow-by you get power LOSS.. So, if you have blow-by (which you do) and you Lose power (which happens with blow-by) then you will now be over-fueling the cylinder, contaminating the intake charge (due the blow-by) which, in turn, lowers charge purity, which in turn, lowers power... So, now you have made your engine make less power BUT you are still feeding it with the same fuel (via carb jets) for the stock power.. So, now you have created a over-fueling (rich) condition inside the engine.. Rich conditions COOL the piston which is needed because of the ring over-load, and this same rich condition also aids in the power LOSS.. you can not make power with an overly rich condition... So, it is a cycle that repeats over and over.. ring over-loads, charge density lessens, rich conditions occurs, power ouput is dimished, piston cools, ring seals normal again, back to stock power (or close to it) rinse, wash, and repeat..It is VERY hard to seize an engine with a very rich condition... This is a very good reason for BRP to use a single ring. Less engine failure due to over-fueling.

Amen wish i had taken pictures of the blow by in the last 026 i built.prime example of rings not seating properly.transfers,crank case,crank etc was covered it black goop.rings were loose in the lands.the fellow that i got it from couldnt figure out why he couldn't get the carb set right even after a total clean and rebuild.after a new piston and rings and a soak down in b12 it was running perfectly.

 

[Miller Mod Saws]

Here's a picture of Brian's piston. I drove it in as far as possible.......and it ended up a hair too long. I used a cut off wheel and ground it down, and out of the way.

This is almost exactly what I was thinking. I wanted to use both pins but locate on to the right of center a couple mm and the other to the left.

 

[mdavlee]

Probably for the best.

I'm a firm believer that two rings will get the heat out of the piston, and into the fins better.

But.......most XPWs I do are saws that are not really worksaws in the true sense of the word.

Yep. Unless someone says they want it on the edge of actually blocking big wood all day I try to keep both rings. I wouldn't run a saw that came with 2 on a mill with one. Now if we could get a 1.5mm single ring piston I would use it all I could.