New Saw Update

[Fifelaker]

What ratio do you use for shrubbery being circumsized at synagogues? :smirk:

I don't know about that, but I'm pretty sure Brazilians skip the oil entirely and go with 100% wax for removing shrubbery.

Sounds painful...

http://youtu.be/C660_Ag1UFk watch this :cheese:

 

[varna]

Why 40:1?
50:1 will leave less residue on the transfer ports and will be plenty of lubrication especially with 100LL

It's a long read, but very informative:

http://motocrosshideout.com/2-stroke-dirt-bike-pre-mix-101/

 

[Battenkiller]

But aren't we running our saws WOT all the time? Wouldn't more oil be better? I don't know, I'm still learning all this stuff.

I was told I was wrong about the 50:1 ratio being better on another thread, and I have been thinking about that. This article is saying the same thing, except no one here is re-jetting their carbs AFAIK. So, maybe the way the saw comes stock is the ratio you should use? My saw manuals all say use synthetic at 50:1, so I'm sticking to that until I can hear something more definitive regarding saws, not cycles.

Interesting that when I was talking to Brian Ruth (he and his wife wrote a highly regarded beginner's chainsaw book) about the small RedMax carving saw that he helped develop, he said to run it 80:1 with a good synthetic oil (I use Amsoil Saber). According to him, the saw will have more power in the cut (and a lot less smoke in your face) at 80:1, and it will run cooler and last a lot longer. This opinion is shared by the Japanese manufacturer that sponsors him. Brian is an internationally known carver and has been at it for over 30 years, so he ought to know something about saws.

As I said... still learning this stuff.

 

[Battenkiller]

What ratio do you use for shrubbery being circumsized at synagogues? :smirk:

I don't know about that, but I'm pretty sure Brazilians skip the oil entirely and go with 100% wax for removing shrubbery.

Sounds painful...

I imagine so. I've heard that Brazilian shrubbery grows very thick and dense.

 

[smokinj]

But aren't we running our saws WOT all the time? Wouldn't more oil be better? I don't know, I'm still learning all this stuff.

I was told I was wrong about the 50:1 ratio being better on another thread, and I have been thinking about that. This article is saying the same thing, except no one here is re-jetting their carbs AFAIK. So, maybe the way the saw comes stock is the ratio you should use? My saw manuals all say use synthetic at 50:1, so I'm sticking to that until I can hear something more definitive regarding saws, not cycles.

Interesting that when I was talking to Brian Ruth (he and his wife wrote a highly regarded beginner's chainsaw book) about the small RedMax carving saw that he helped develop, he said to run it 80:1 with a good synthetic oil (I use Amsoil Saber). According to him, the saw will have more power in the cut (and a lot less smoke in your face) at 80:1, and it will run cooler and last a lot longer. This opinion is shared by the Japanese manufacturer that sponsors him. Brian is an internationally known carver and has been at it for over 30 years, so he ought to know something about saws.

As I said... still learning this stuff.

Nothing wrong with 50:1, Now a big saw running long cuts its not a bad "Idea" to run 40:1. Amsoil like you said 80:1 fine or even 100:1 if I was mixing just for my 192t.

 

[TMonter]

Why 40:1?
50:1 will leave less residue on the transfer ports and will be plenty of lubrication especially with 100LL

It's a long read, but very informative:

http://motocrosshideout.com/2-stroke-dirt-bike-pre-mix-101/

He still doesn't talk about the long term effects of that much oil in the combustion chamber and the carbon buildup on surfaces. Granted you have to have the engine jetted properly with a lower oil ratio, but that is something you should be doing anyway.

He's also completely off on the combustion temperatures. The adiabatic flame temperature for a gas mixture is far lower than he's claiming.

 

[Battenkiller]

He still doesn't talk about the long term effects of that much oil in the combustion chamber and the carbon buildup on surfaces. Granted you have to have the engine jetted properly with a lower oil ratio, but that is something you should be doing anyway.

He's also completely off on the combustion temperatures. The adiabatic flame temperature for a gas mixture is far lower than he's claiming.

Yeah, those motocross guys are like the race saw guys. They'll mod a saw to death for 2 seconds run time.

I'd think that the carbon buildup would lead to overheating eventually, or at least hot spots developing. Just like with stoves, I'll need more proof before I'll deviate from what the expert engineers say belongs in the saw.

 

[TMonter]

He still doesn't talk about the long term effects of that much oil in the combustion chamber and the carbon buildup on surfaces. Granted you have to have the engine jetted properly with a lower oil ratio, but that is something you should be doing anyway.

He's also completely off on the combustion temperatures. The adiabatic flame temperature for a gas mixture is far lower than he's claiming.

Yeah, those motocross guys are like the race saw guys. They'll mod a saw to death for 2 seconds run time.

I'd think that the carbon buildup would lead to overheating eventually, or at least hot spots developing. Just like with stoves, I'll need more proof before I'll deviate from what the expert engineers say belongs in the saw.

Exactly. From everything I've read and from pictures I've seen of saws broken down and my own equipment, I'll stick to 50:1 with a high quality synthetic oil and make sure the saw is properly tuned and tached at slightly rich. Last time I broke down a saw for a friend we had tuned up for him (big bore kit) the piston/cylinder was almost spotless and there was no significant wear on anything. He was running M2T @ 50:1 and we had it tuned for 1/4 turn rich below peak RPM's.