Another chainsaw dyno...

[Sawrain]

My theory is we are rarely using the full power. Either we don't have the gearing right so chain speed isn't optimized or we don't have an aggressive enough chain to use the power and we're just spinning wheels. It's like drag cars. Equal weight you would assume more power wins, and it often does but not always and sometimes the underdog smokes the big dog. it's all about getting that power used. You've got the driver/operator. Transmission and clutch/clutch and sprocket, and tires/chain. They all go all long way to be the first down the track or through the wood.

I agree with this, but feel specifically it is about efficient use of power.

If a saw is at full throttle and steady state rpm it will for sure be putting out the power that these (fantastic) dyno graphs here show, the work is being done.

It is up to us to optimise the gearing and chain to cut in the most Efficient manner to best utilise the power , all in the chain as they say.

If chain load isn’t enough to utilise a saws peak power, rpm will continue to climb past peak until power falls off to match the load, same as wheel spin, if you don’t lift throttle you either hit the rev limiter or revs climb past peak power until power drops to match the traction available.

 

[RI Chevy]

Each saw and chain must be tuned to each other to maximize efficiency.

 

[Sawrain]

My chain knowledge is barely more than using factory angles, and knowing that they dolphin, I really need to learn more about one of the most important aspects of chainsaws.

 

[Red97]

Is a box stock stihl rs better suited to the 6 hp of the 461, or 7 to of the 661?

Is off the roll chain testing actually giving a handicap to the more powerful saw because it is dialed into 5.5/6hp?

Food for thought

 

[mgr1]

Each saw and chain must be tuned to each other to maximize efficiency.

More hp and torque how more you can file the raker down.

10hp saw with a 5 times sharpend chain without touching the raker wil not cut faster than a 5hp saw with perfect sharpend chain and correct rakers.

Mistery solved

 

[dall]

Is a box stock stihl rs better suited to the 6 hp of the 461, or 7 to of the 661?

Is off the roll chain testing actually giving a handicap to the more powerful saw because it is dialed into 5.5/6hp?

Food for thought

exactly factory chains are made with lower hp saws in mind such as a 60cc saw
most saws sold are in the lower hp and price range

 

[Red97]

Actually pretty excited. Fedex just dropped off my 86cc hybrid build. Had spent the last couple months out in Oregon and Colorado cutting timber. Got a couple extra mods along the way..

Very curious to see what kind of to can cone from a 60cc chassis...

Gws dall 036 got a new (60cc) champ on the way hehe

 

[Duane(Pa)]

Is a box stock stihl rs better suited to the 6 hp of the 461, or 7 to of the 661?

Is off the roll chain testing actually giving a handicap to the more powerful saw because it is dialed into 5.5/6hp?

Food for thought

If I had to guess, it’s probably dialed for durability in clean cutting conditions. Very few loggers are as esoteric as we are about stuff. They just trigger the shots day after day.

 

[dall]

Actually pretty excited. Fedex just dropped off my 86cc hybrid build. Had spent the last couple months out in Oregon and Colorado cutting timber. Got a couple extra mods along the way..

Very curious to see what kind of to can cone from a 60cc chassis...

Gws dall 036 got a new (60cc) champ on the way hehe

View attachment 251392

lol if its 86cc its in a bigger class now lol

 

[leadfarmer]

Actually pretty excited. Fedex just dropped off my 86cc hybrid build. Had spent the last couple months out in Oregon and Colorado cutting timber. Got a couple extra mods along the way..

Very curious to see what kind of to can cone from a 60cc chassis...

Gws dall 036 got a new (60cc) champ on the way hehe

View attachment 251392

Wtfisthat? Dent puller special ? [emoji23]

 

[Red97]

lol if its 86cc its in a bigger class now lol

But but, it's tag says 59.8 cc....

 

[dall]

But but, it's tag says 59.8 cc....

lol

 

[Red97]

Wtfisthat? Dent puller special ? [emoji23]

Well....

I was thinking more along the lines of a leaf blower.

But whatever floats your boat.

Lol

 

[huskyboy]

I’m not surprised a 036 is current champ for a “true” 60cc saw. Look at the size of the carb on it... same as a 70cc saw. Look at the exhaust outlet... it uses the same gasket as a 85cc 064 and the muffler volume is almost the same as a 70cc 044. It’s easy to see why the potential is there. I’m actually quite amazed that 79cc 7900’s make the power they do on pretty much the same zama carb as the 036 save for a different choke/throttle setup. That 16mm venturi is TINY for a 80cc saw. It was easy to see why it was a gain when I bored it out and jetted it better. A HD or a WJ/HS swap would probably net even more gains. It would be interesting to dyno test carb combinations and see what actually works.

 

[dall]

I’m not surprised a 036 is current champ for a “true” 60cc saw. Look at the size of the carb on it... same as a 70cc saw. Look at the exhaust outlet... it uses the same gasket as a 85cc 064 and the muffler volume is almost the same as a 70cc 044. It’s easy to see why the potential is there. I’m actually quite amazed that 79cc 7900’s make the power they do on pretty much the same zama carb as the 036 save for a different choke/throttle setup. That 16mm venturi is TINY for a 80cc saw. It was easy to see why it was a gain when I bored it out and jetted it better. A HD or a WJ/HS swap would probably net even more gains. It would be interesting to dyno test carb combinations and see what actually works.

the choke is a hold back on the 026 and 036
my 036 still has the original carb not drilled and limiters still on the carb
i dont see how you can say venturi is bigger with the shape it has in the middle
so lets hear more excuses

 

[huskyboy]

i dont see how you can say venturi is bigger with the shape it has in the middle

The shape in the middle you refer to is the “venturi” which is about 16-16.6mm on the zama C3M depending on what version you have. A Walbro HD12 a 372 or HD16 off a 460 have a larger 17.46mm venturi by comparison. The throttle bore is also slightly larger on the HD12 and HD16 than the C3M.

 

[dall]

The shape in the middle you refer to is the “venturi” which is about 16-16.6mm on the zama c3m depending on what version you have.

the middle part is not 16mm the outside ends may be close to 16mm im not gonna waste my time measuring
if we was to do that we could go to a different thread where you and another suckpump have been running down the 500i when you have very limited time running a 500i

 

[RI Chevy]

Actually pretty excited. Fedex just dropped off my 86cc hybrid build. Had spent the last couple months out in Oregon and Colorado cutting timber. Got a couple extra mods along the way..

Very curious to see what kind of to can cone from a 60cc chassis...

Gws dall 036 got a new (60cc) champ on the way hehe

View attachment 251392

Looks like an elephant trunk

 

[Red97]

Well decent numbers, but smoke rolling from the clutch the entire time leads me to believe it's not fully locked.

9.2 at 9800 5.8ftlb at 5800 see if it can do it again with a clutch and carb swap. This one isn't tuning well at all...

 

[dall]

Well decent numbers, but smoke rolling from the clutch the entire time leads me to believe it's not fully locked.

clean it and redo