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Huskybill

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I often wondered why the two stroke chain saw engines don’t follow the dirtbike engines. The dirtbike engines use a rotating or gillitine valve on the upper exhaust port to raise the exhaust port starting at mid throttle to the high end on the throttle. I figured a cable like the throttle cable can be run to a rotating exhaust port. Not to load the engine with a mechanical governor. It would be a increase in power at the high end and still have torque starting off the bottom.
 
In the dirt bike world they refer to them as power valves. Both my 1996 Honda CR250R and 2001 Yamaha YZ125 had them. One time for giggles I locked the power valve on the 250 open to see what it was like. Holy moly....it had no low end but then the power hit like a freight train. Lol. Let’s just say it didn’t stay locked open long. With the power valve working it had a lot of low end and the power still hit but not nearly as hard as it being locked open. I miss that bike.
 
Because saws are designed to be basically run at idle or at WOT. Where a dirtbike isn't.
 
Holey is exactly right on this issue. Yes the 2 stroke saw could have at least 400% more power, but at a cost to everyone. The EPA standards would like if all 2 smokes were non existent. Just like blowers I think you will see battery and 4 strokes. Thanks
 
Does anyone know where the powerband is on a chainsaw? I want to put a bigger one on my saw but I can't seem to find it. :dumb:
I bought this one but can't find where to install it either. If you find out, let me know.
4ec72c121dc31894273b5ff0ae807f0a.jpg


Sent from my Moto G (4) using Tapatalk
 
There is no need for the added weight and complexity of power valves in an engine designed for wide open throttle operation.

Imo
This is exactly why.

Chainsaws are designed with performance balanced with reliability. Mx bikes are designed for performance mostly. Mx bikes on the track are looked over and sometimes rebuilt after every race, they can afford the extra complexity for that added performance.
Guys or gals felling trees in the middle of no where can’t afford to have a problem.
 
Battery, maybe. But 4 stroke is to heavy and stops working when you hold it in an angle.
For chainsaws, I think 2 strokes will stay for a while.



Verstuurd vanaf mijn SM-G955F met Tapatalk


In larger saws, I can see 2 Smokes being around for quite awhile, can you imagine how many battery packs a felling crew would have to pack around on a large job cutting Big Wood?:confused:

Ooopps, Never Mind, I was mistakenly thinking that the Government in General, and the EPA in particular would use Logic, or Common Sense:(:laughing::laughing:

Now if it were left up to the Free Market, you would see some smaller, and mid size saws developed for home owners, occasional users and Arborist's light work.

Please Forgive my thinking that the Government would be involved in Logical thinking



Doug :cheers:
 
Problem with batteries is they suck, and they haven’t really changed in a century. Unless the best batterie right now can be re designed to hold 20 more times the power and amps per volume, gas engines are going to be around until the fossil fuels run out.
Last time I checked we have enough fossil fuels to last a couple more hundred years! I believe that was in the US alone, that’s not counting Canada which probably has just as much
 
This topic has been done over and over. The more current thing to wonder about might be, will Husqvarna that makes chainsaws use the transfer port injection that KTM motorcycles has brought to market lately? After all KTM has to pay a licensing fee to use the Husqvarna name on a line of motorcycles from what is posted on motorcycle forums. The other choice might be to pay Stihl for the use of their fuel injection ideas.
 
Problem with batteries is they suck, and they haven’t really changed in a century. Unless the best batterie right now can be re designed to hold 20 more times the power and amps per volume, gas engines are going to be around until the fossil fuels run out.
Last time I checked we have enough fossil fuels to last a couple more hundred years! I believe that was in the US alone, that’s not counting Canada which probably has just as much
Lithium Ion batteries in my opinion really are a significant change from what was around a century ago. My take is folks expect too much from a battery. The air a piston engine uses weighs much more than the fuel it uses. The Lithium ion battery has a more constrained temperature window than a gasoline piston engine. I think a fuel cell could use air and fuel but they are too complex for the application here.

The peak oil predictions were not very accurate it turns out.
 
Franny K wrote:

The peak oil predictions were not very accurate it turns out.



What? I thought that we ran out of Fossil fuels in 1987?, or was 1995? or was it maybe that Magical year 2000, when all kinds of things were going to change?

I Stihl haven't seen those "Jetson's" style Flying Cars that were promised by again that Magical year 2000

Battery technology HAS Improved over the last Century, but stihl is no where near replacing Internal Combustion Engines in MANY applications.

ICE, both Engines and Law Enforcement;) will be around for quite awhile, I suspect


Doug :cheers:
 
Lithium Ion batteries in my opinion really are a significant change from what was around a century ago. My take is folks expect too much from a battery. The air a piston engine uses weighs much more than the fuel it uses. The Lithium ion battery has a more constrained temperature window than a gasoline piston engine. I think a fuel cell could use air and fuel but they are too complex for the application here.

The peak oil predictions were not very accurate it turns out.

The addition of brushless motors has really upped the game as well. We now have cordless tools with more power than their corded counterparts.
Milwaukee has a nice cordless saw out, and its got good reviews as to runtime. Id guess its much more biased towards the occasional user, but a local tree company has one battery saw they use pretty often. They seem to really like it for small simple stuff.

Kinda getting off topic, but since Ive been looking at similar cordless tools, I thought Id throw in my .02.
 
The addition of brushless motors has really upped the game as well. We now have cordless tools with more power than their corded counterparts.
Milwaukee has a nice cordless saw out, and its got good reviews as to runtime. Id guess its much more biased towards the occasional user, but a local tree company has one battery saw they use pretty often. They seem to really like it for small simple stuff.

Kinda getting off topic, but since Ive been looking at similar cordless tools, I thought Id throw in my .02.

It has, there is no disagreement there, but it’s just not good enough to replace gas engines right now. Charge times are just a hinderance as power per volume of a battery.

On the topic of the future of gas engines it’s still very strong. I think the future is in a new type of fuel cell that generates power, possibly hydrogen through water separation. Hydrogen is the most abundant element in the universe and water is the most abundant compound on this planet.

Truth be told we really won’t see anything change until the fossil fuels run out. There’s too much money at stake for countries that extract and sell it. You don’t sit on billions of dollars in a product that’s still good and just say “well I know it’s bad for the environment so let’s just stop extracting and selling it and figure something else out” lol money truly runs this planet and anyone who doesn’t think so is naive.
 
It has, there is no disagreement there, but it’s just not good enough to replace gas engines right now. Charge times are just a hinderance as power per volume of a battery.

On the topic of the future of gas engines it’s still very strong. I think the future is in a new type of fuel cell that generates power, possibly hydrogen through water separation. Hydrogen is the most abundant element in the universe and water is the most abundant compound on this planet.

Truth be told we really won’t see anything change until the fossil fuels run out. There’s too much money at stake for countries that extract and sell it. You don’t sit on billions of dollars in a product that’s still good and just say “well I know it’s bad for the environment so let’s just stop extracting and selling it and figure something else out” lol money truly runs this planet and anyone who doesn’t think so is naive.
Bingo! I laugh when I see college kids think they’re gonna turn everything “green”. You won’t do that until every oil company has gotten every last drop of oil from every crevice of this earth. Simple as that.
 
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