Dolmar 64xx/73xx/79xx series, smurfs and solo 665/675/681 thread

[T.Roller]

Glass of whiskey, tailgate, heckling...

That sounds like a better time

 

[Lightning Performance]

Some single barrel might inspire me to carve something Alabama related...

Maybe..

Single malt?

 

[wcorey]

I keep studying this slabside piston, nice looking piece. The wrist pin is amazingly light looking. I wonder if it’s tapered? I believe the ring is a 1.2mm if I’m not mistaken, that surprised me too. Less friction than a 1.5

My notes have the newer piston at 11.3 grams lighter (bare without wrist pins), not sure where I got that info.
Looks like the sides have a little more clearance than the windowed version around where it meets the lower transfers.
Not sure what use the windows would've had here in any case.

A little out of the norm to have a single 1.2mm ring...

 

[huskyboy]

My notes have the newer piston at 11.3 grams lighter (bare without wrist pins), not sure where I got that info.
Looks like the sides have a little more clearance than the windowed version around where it meets the lower transfers.
Not sure what use the windows would've had here in any case.

A little out of the norm to have a single 1.2mm ring...

Thanks for the good info Bill, I was questioning what benefits a windowed piston would have in a bottom fed cylinder as well myself.

 

[Lightning Performance]

Thanks for the good info Bill, I was questioning what benefits a windowed piston would have in a bottom fed cylinder as well myself.

Cooling

 

[David Young]

That sounds like a lot of work.

I’d rather sit on a tailgate and heckle..

What if you could only pick 2?

 

[David Young]

Strong. I am giving it to Dan

Which one is this Jeff?
Did it have too much power and scare you?

 

[David Young]

Thanks for the good info Bill, I was questioning what benefits a windowed piston would have in a bottom fed cylinder as well myself.

It may also make it more free. If the base has less compression that phase of pumping would be easier

 

[RI Chevy]

Which one is this Jeff?
Did it have too much power and scare you?

Yes. I bought it about a month back in CT. Paid $350 for it. Came with bar and everything. Seems to have a little extra uummph. Haven't really opened the covers.
I am just used to Stihl. I'll just give it away to someone.

 

[Hedgerow]

Cooling

And flow to the lower transfers.
Real estate is at a premium in those saws.

 

[Hedgerow]

What if you could only pick 2?

Whiskey and heckling..

I can do that standing up if I have to.

 

[huskyboy]

Very interesting discussion. I am guessing they changed the piston for a reason. They probably spend a lot of $ on R/D, plus probably computer aided designs. I’m just trying to figure out that reason.

 

[Adirondackstihl]

Very interesting discussion. I am guessing they changed the piston for a reason. They probably spend a lot of $ on R/D, plus probably computer aided designs. I’m just trying to figure out that reason.

Fine line between performance, emissions and manufacturing processes

 

[wcorey]

I also heard somewhere there were bottom end issues at some point so lighter piston and lower rev limit.

 

[Adirondackstihl]

I also heard somewhere there were bottom end issues at some point so lighter piston and lower rev limit.

First I heard of bottom end issues on this platform.
I know there were bottom end issues on the 5100S (spun bearings).

 

[Hedgerow]

First I heard of bottom end issues on this platform.
I know there were bottom end issues on the 5100S (spun bearings).

Most of those were due to stupid high compression and too much heat.
Easily avoidable if you tune good and run a sharp chain.
Those little *s-words did have a ton of comp for a stock saw. Some were well north of 200 lbs.

 

[Hedgerow]

Well lookie here....

Right next to me in the office..

 

[Adirondackstihl]

Well lookie here....

Right next to me in the office..

View attachment 137220

I’ve got the same wun! Or......maybe that’s mine? I gotta go check....

 

[T.Roller]

Yes. I bought it about a month back in CT. Paid $350 for it. Came with bar and everything. Seems to have a little extra uummph. Haven't really opened the covers.
I am just used to Stihl. I'll just give it away to someone.

Well I'll take it

 

[huskihl]

Well lookie here....

Right next to me in the office..

View attachment 137220

I’ve got the same wun! Or......maybe that’s mine? I gotta go check....

I gots the same one too...