18" suga bar on a 660 stupid or cool

[Hats]

Cheers timber cutter

[stihlmadasever]

better:ahhhhh:

[Stubby]

Picture upside down because im crap with an ipad lol. Do i check if its running lean at top end by stopping it just after thrashing it like after ringing up big timber then look at spark plug?

 

Its called a " plug chop " I think . Bury it in the wood flat out and cutting hard then switch it off mid cut . Don't shut the throttle .Then check plug . You need to see how its fueling when working .

Edited October 11, 2015 by Stubby

[peatff]

Picture upside down because im crap with an ipad lol. Do i check if its running lean at top end by stopping it just after thrashing it like after ringing up big timber then look at spark plug?

 

It's there again. Can anybody tell me why changing a bar should increase top end revs or make the mixture lean ? I mess about with engines rebuilding etc and am fairly competent at setting mixtures and such then something like this crops up again and I start to wonder how these things can affect top end and stuff when it's set up with the H & L screws. I can see how it will get to the top speed quicker but not how it can increase it or change fuelling.

[Stubby]

It's there again. Can anybody tell me why changing a bar should increase top end revs or make the mixture lean ? I mess about with engines rebuilding etc and am fairly competent at setting mixtures and such then something like this crops up again and I start to wonder how these things can affect top end and stuff when it's set up with the H & L screws. I can see how it will get to the top speed quicker but not how it can increase it or change fuelling.

 

I think its just the fact that the shorter bar and chain combo create less drag so the power head does not have to work so hard so may rev a little higher . If you raise the gearing by fitting an 8 pin you will get faster chain speed in fresh air but will sacrifice a little torque when in the cut which may bring the revs back down a little . Of course if you have an A/T saw its all academic as it will retune itself .

[njm]

It's there again. Can anybody tell me why changing a bar should increase top end revs or make the mixture lean ? I mess about with engines rebuilding etc and am fairly competent at setting mixtures and such then something like this crops up again and I start to wonder how these things can affect top end and stuff when it's set up with the H & L screws. I can see how it will get to the top speed quicker but not how it can increase it or change fuelling.

 

Less load on the motor in or out of the cut , saw will rev out on an 18" bar so it requires a bit more fuel on the H screw to control peak rpm .

Take the line out of a strimmer and see what happens .

[Cut4fun]

Ran a 16" on my ported 066. Also ran 32"

[Cut4fun]

Playing with 16" and square filed chain.

Edited October 12, 2015 by Cut4fun

[Johny Walker]

had a 15" on my 660, to cut some massive beech rings down ,

[Arbtech Tree Services]

Also used 18" bar on 660 to noodle 6' Beech rings as dealer didn't have a 16" - no issues.

 

Regards,

 

Steve.