torque vs chainspeed

[Moparmyway]

Try extra banana's ,they work pretty good .They are those tunnels next to the intake in this 460 jug ,Look like banana's to me anyways ,and a monkey put them in there .

All of the saws he does should come with those stickers !!

 

[jeepyfz450]

Just build the best engine you can......

There is no better teacher than experience. I've done hundreds and hundreds of saws......and I'm still learning.

Here's a tidbit that will help anyone see what really makes a saw get through the wood faster. Build several of the same model........do them all a little different. Keep good notes, make several cut in bar length wood with each saw.......in the same wood.....with the same bar & chain. Video all the cuts, and review them with a stopwatch. Listen carefully to each saw as it is leaned on, when it is just pulling itself, and when it idles down after the cut.

If you really wanna see what works........this is now you'll get there.

The days of me coming on here and saying what works in each model are over. How you build a saw.......that's great. I could care less how anyone elses saws run.......the only ones that matter to me are mine.

Wednesday, January 28th 2015........and I'm knee deep in studying different combos on the MS660.

View attachment 398892

I don't see a 056magii top end in there. You know how they run.

 

[Chris-PA]

OK, I'll be pedantic, because proper terminology matters.

I can make more torque than any saw with my arm and a wrench.

At 0 rpm.

Torque does not do work, the proper term is power, which is torque X rpm. The issue is the shape of the power curve you want, not torque vs. power.

If you have a higher chain speed with the same load you are producing more power and doing more work.

If you must reduce the load to get a higher chain speed then you may not be producing any more power.

 

[Mastermind]

I don't see a 056magii top end in there. You know how they run.

I might do something like that for a toy.........but I can't do it for customers.

 

[MillerModSaws]

Just build the best engine you can......

There is no better teacher than experience. I've done hundreds and hundreds of saws......and I'm still learning.

Here's a tidbit that will help anyone see what really makes a saw get through the wood faster. Build several of the same model........do them all a little different. Keep good notes, make several cut in bar length wood with each saw.......in the same wood.....with the same bar & chain. Video all the cuts, and review them with a stopwatch. Listen carefully to each saw as it is leaned on, when it is just pulling itself, and when it idles down after the cut.

If you really wanna see what works........this is now you'll get there.

The days of me coming on here and saying what works in each model are over. How you build a saw.......that's great. I could care less how anyone elses saws run.......the only ones that matter to me are mine.

Wednesday, January 28th 2015........and I'm knee deep in studying different combos on the MS660.

View attachment 398892

Awesome advice. Good luck on your 660 adventure.

 

[jeepyfz450]

I might do something like that for a toy.........but I can't do it for customers.

I hear you. I wouldn't do it to my beloved 660 but Bret isn't right in the head

 

[Mastermind]

I hear you. I wouldn't do it to my beloved 660 but Bret isn't right in the head

That saw is a hoot to run.

I suspect I know what helps it......

 

[jeepyfz450]

Lol I suspect you do aswell

 

[wcorey]

Torque does not do work, the proper term is power, which is torque X rpm. The issue is the shape of the power curve you want, not torque vs. power.

If you have a higher chain speed with the same load you are producing more power and doing more work.

If you must reduce the load to get a higher chain speed then you may not be producing any more power.

Agreed, and the 'width' of the power curve is also a considerable factor, 'shape' can dictate 'width' to some degree...

Of course I want it all, a wide, useable, forgiving power band that will give me chain speed but can also be dogged down a bit and still keep chugging along. Up for debate how attainable that is so err on the side of 'midrange power' if need be (which is probably what most people mean when referring to 'more torque')...

The easiest way for me to relate to this is looking at a dyno chart. My experience with dyno results and useable power output is mostly with bikes but that stuff can still apply here.

Peak torque occurs at lower rpm than peak hp. The best useable power is typically in the area that spans between peak torque and peak hp. How flat the torque curve is and the relative distance (in rpm) of peak torque from peak hp can give an idea of how wide the effective useable power band is.

With bikes, lower hp but wider power band can be faster in many circumstances than higher hp with narrow power band in part because it’s easier to apply the power in an effective way. It really depends on the operator but everything is just less critical and more forgiving, you can be more ham fisted and get away with it, lol…

 

[thomas1]

OK, I'll be pedantic, because proper terminology matters.

I can make more torque than any saw with my arm and a wrench.

At 0 rpm.

Torque does not do work, the proper term is power, which is torque X rpm. The issue is the shape of the power curve you want, not torque vs. power.

If you have a higher chain speed with the same load you are producing more power and doing more work.

If you must reduce the load to get a higher chain speed then you may not be producing any more power.

What gives you the ability to increase load while maintaining chain speed?

 

[Mastermind]

Starburst Fruit Chews?

 

[wcorey]

What gives you the ability to increase load while maintaining chain speed?

More power...

 

[Mastermind]

Fireballs.

I eat a lot of fireballs.

 

[Chris-PA]

Peak torque occurs at lower rpm than peak hp. The best useable power is typically in the area that spans between peak torque and peak hp. How flat the torque curve is and the relative distance (in rpm) of peak torque from peak hp can give an idea of how wide the effective useable power band is.

With bikes, lower hp but wider power band can be faster in many circumstances than higher hp with narrow power band in part because it’s easier to apply the power in an effective way. It really depends on the operator but everything is just less critical and more forgiving, you can be more ham fisted and get away with it, lol…

In a sense, for something like a bike that is accelerating through the rpm range, it is the area underneath the hp vs. rpm plot that is important. I'm still thinking about what it means for something like a chainsaw which is more of a single speed engine. I'm not sure if you want the same spread between the torque peak and hp peak - maybe just want them to bracket the normal operating rpm? Still, once you pull it down below the torque peak you're probably going to be bogging.

 

[HuskStihl]

"Torque" isn't even a real thing in engine world, just a cool word to throw around that people understand. It is simply a mathematical function of power and rpm. It is a "feel" word. When somebody says they like torque, they mean they like a saw that produces good power at low (relatively) RPM's. I'm impressed that saw builders can change so much with relatively few variables (no camshaft, variable valve timing, variable exhaust pressure, etc)

 

[thomas1]

More power...

And since the chain speed is the same, how does this magical addition of power occur?

 

[thomas1]

Fireballs.

I eat a lot of fireballs.

Have you tried Blue Star Ointment?

 

[Joe Kidd]

Fireballs.

I eat a lot of fireballs.

Yes! Quite tasty.

 

[HuskStihl]

And since the chain speed is the same, how does this magical addition of power occur?

Power is work divided by time. Even if chain speed stays the same, the amount of work can be changed by altering the force applied to the saw

 

[Mastermind]

Whole grains are hard to digest.....