5100S Tuning: Target RPM Poll

[CHEVYTOWN13]

That windsor bar looks bad ash on a 5100. Looks real good.

 

[Termite]

Yes, woodyman, my 5100 is right around 200psi.

My new 420 was 195 out of the box. After a couple of tanks it pumped 210psi. I think they both could use a high octane fuel.

 

[wanab]

One Dolmar dealer tells me 87 octane, non-alcohol, Opti-II, & some Seafoam ...

.......... :bang:

wow, just wow,



if i had to do all that just to keep a saw alive.

 

[grandpatractor]

I broke my 5100 in on 40.1,WoodlandPro Synthetic,92 octane at 13,800 WOT.Now just broke in I run the same mix but have it up to 14,300 WOT.Anybody else have 200psi cold.

Never checked mine. Feels like it tho. It pull over hard compared to the rest of my saws.

 

[Trigger Man]

I broke my 5100 in on 40.1,WoodlandPro Synthetic,92 octane at 13,800 WOT.Now just broke in I run the same mix but have it up to 14,300 WOT.Anybody else have 200psi cold.

Woody man did you put an extra covering on your front handle or did it come that way?

 

[grandpatractor]

Woody man did you put an extra covering on your front handle or did it come that way?

Heated Handles.

 

[Trigger Man]

Heated Handles.

Ah, yes. I forgot.

 

[SawTroll]

Woody man did you put an extra covering on your front handle or did it come that way?

HMMMMMM???? - I thought all 5100Ss came with a rather thick metal handlebar, with plastic tubing on them???

 

[Trigger Man]

HMMMMMM???? - I thought all 5100Ss came with a rather thick metal handlebar, with plastic tubing on them???

They do, but the one on mine is not ribbed like the one in the pic, and you can tell that there is a cover under neith the one on top. Or at least i can see were the under neith cover ends.

 

[tharrison57]

wow, just wow,



if i had to do all that just to keep a saw alive.

And from what I heard the other day, he may be a FORMER dealer .....

Oh, and that was his "standard two cycle fuel", 50 gallons at a time.

 

[MCW]

Running a higher octane fuel doesn't hurt, you just aren't deriving all the benefit the fuel can deliver if the saw is stock, although one benefit is that the high octane fuels often burn more cleanly than lower octane ones as they have detergents included as part of their additive package.

Good reply once again Rick.
You'd know I presume mate being involved with motor racing at one stage but I'm also of the opinion that by using a higher octane fuel you also increase your buffer in a lean out scenario, at least that's what I remember reading somewhere for modified cars regarding pinging

I'm certainly no 2 stroke guru but I presume the higher octane fuels would be beneficial with modified saws, particularly those with advanced timing.

 

[Analyst Man]

Octane

Running a higher octane fuel doesn't hurt, you just aren't deriving all the benefit the fuel can deliver if the saw is stock, although one benefit is that the high octane fuels often burn more cleanly than lower octane ones as they have detergents included as part of their additive package.

True, a cleaner burn is probably a good thing. That may be why Echo and Stihl recommend 89 octane while Husky and Dolmar recommend 87. Not sure though.

Good reply once again Rick.
You'd know I presume mate being involved with motor racing at one stage but I'm also of the opinion that by using a higher octane fuel you also increase your buffer in a lean out scenario, at least that's what I remember reading somewhere for modified cars regarding pinging :cheers
I'm certainly no 2 stroke guru but I presume the higher octane fuels would be beneficial with modified saws, particularly those with advanced timing.

The thing I read about higher octane was that it burns slower, which helps prevent pre-ignition and pinging. I’m no guru either, but that’s what I recall reading.

 

[Analyst Man]

High performance engines

Got this from the article in the attachment.

"One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel."

I'm probably reading between the lines but that sounds like the manufactures who recommend higher octane fuels (89 vs 87) are making a more "high-performance engine".

http://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/question90.htm

 

[Islander]

I'm a little skeptical of the 87 octane spec for a 5100S. Probably fine with the 510, 460, etc...but I gota believe a 5100S likes the higher octane. Maybe the 420 too at 200+ PSI?

I need to explore the ethanol free world here in Vermont...must be someone who carries high test.

Seems like this would be a good subject for a web site or goggle map. I don't mind paying more for ethanol free...just need to know where to get it.

Anyone know of a list of ethanol free gas sources? Seems like a great place to advertise outdoor power equipment...also a great product for a saw shop to carry. Gas purchases might drive chain, oil, etc sales as well...

 

[Islander]

That was easy

Google found this one...

http://pure-gas.org/

Anyone use this site for finding ethanol free gas?

 

[Analyst Man]

Good work! Hard for me to belive that there's only one station in IL and it's in
East Peoria almost 100 miles from me.

 

[wanab]

im not sure how much you cut but just get some race gas and tune you saws for it and forget about it. the stuff lasts forever.

:biggrinbounce2:

 

[Termite]

Wanab,"im not sure how much you cut but just get some race gas and tune you saws for it and forget about it. the stuff lasts forever."

I was using racing gas and it gummed up my piston and ring real good. I believe racing gas I used had a lot of additives that caused the problem. I switched to 110AV gas.

 

[woodshed]

13,000, they last longer that way...:hmm3grin2orange:

Scott

 

[tdi-rick]

[snip]
..but I'm also of the opinion that by using a higher octane fuel you also increase your buffer in a lean out scenario, at least that's what I remember reading somewhere for modified cars regarding pinging

I'm certainly no 2 stroke guru but I presume the higher octane fuels would be beneficial with modified saws, particularly those with advanced timing.

Yep, I agree and FWIW I use Ultimate or V Power too, even in the mower and brush cutter. I don't want to have to pull the damned things down to de-carbon them too often.

From all those years ago the first signs of being too lean was detonation, then piston seizing.
It was a fine line, but sometimes you could catch an engine before it seized with those tiny tell tale marks around the crown/ring land region so I'm guessing a boost in octane may give you a very slight margin.