4 stroke chainsaw

[stonykill]

on a bike, you have all this other metal that you can lighten up. My question is, how much heavier is the 4 stroke engine itself? Not the overall weight of the 4 stroke vs 2 stroke bike, but the overall weight difference of the engines. I'm thinking of the weight difference between a 5 hp horizontal briggs, then my 80 cc macs, which are heavy saws by todays comparison. I can't even imagine lugging around an all aluminum 5 hp briggs with a 24 inch bar on it. My back would be out in like 2 minutes.

My suspicion is the bike manufacturers are lightening the frame, wheels, anything else they can to keep the weight about the same. Just a suspicion.

 

[Stihl #1]

DOLMAR:
http://www.arboristsite.com/showthread.php?t=37814
http://www.dolmar.com/98_1097.php
http://www.arboristsite.com/showthread.php?t=33947

 

[robby26wi]

between the 250 2 stroke and 450 4 stroke everything is the same as far as suspension,wheels,tires,brakes and so on....The frames are different but i dont think the 4 stroke frame is made any lighter...

 

[glenn31792]

It will be hard to make a small high hp 4 stroke. You are going to need a 4 valve head (tall
large and very hot) That will probably mean liquid cooling. I don’t want to wear a back
pac with a radiator in it. The cost of rebuilding a crf or yzf dirt bike is wayyyyyy more than
rebuilding a two smoker.
The shops will need way more tools and techs will need schooling in valve guide
Replacement, valve seat replacing, cam timing, setting valve lash.
It will end up being cheaper to buy a OLD style 2 stroke saw than rebuild your 4 stroke saw.
Even companies like honda are having serious problems with todays light 4 stroke mx motors.
http://www.crfsonly.com/forum/viewtopic.php?t=13051

cc for cc a two stroke will put out more hp
62.5cc two stroke saw will make the same hp as a 93.75cc 4 stroke

 

[keith c raymond]

Just a opinion here mind you,But I think when two stroke technololgy cant keep up with epa emissions,and demand is still there,then you will see four stroke saws.Unless it has to be the big manufacturers wont do it.

 

[Goicoechea]

I don't understand why the EPA is worried about chainsaws anyway. The amount of emissions from all of the chainsaws on earth cannot be equal to the output from a couple old coal fired generators. If the money spent developing more efficent chainsaws was directed tward some other pollution generating product it would be better spent....just my opinion...

 

[klickitatsacket]

That's what I was thinking. I love my 4-mix trimmer, despite the slower spool-up. It's a Crazy Torque Monster once it's there.

I would predict you'll see 4-strokes in big saws (felling, big bucking) first, then trickle down to the lighter saws as the technology gets refined. After all, what's another pound or two on a 22 lb beast anyway?

Personal opinion is that the small saws will be the first and most likely the only 4 stroke saws. The average 4 stroke engine compaired to the same power out put of a 2 stroke is 30% heavier. I think that home owners could absorb that in a little saw much better than the pro cutter could. Also spool up is very important to the pro wehn it comes to limbing up a tree.
I think we'll see them but only to help with the over all fleet #'s and they will be small, home owners with a big price difference to entice the novice. Just my opinion, but if it is going to go in that direction then that's how I see it happening.

 

[Timberhauler]

I know when I got my Yamaha YZF 400 back in 99' everyone thought it was going to be too heavy and not have the throttle response and now I don't think there is hardly anyone left running 2 strokes.

I was riding a two stroke until sidelined with injury back in November,and right now I'm about to buy two KTM 300XC's..One to practice on,and one to race on.I will keep riding two strokes until they are no longer available.My issue isn't a lack of power or throttle response,it's starting the thing after a fall..If you have one with electric start,it's not an issue...Most of the smaller guys complain that they are too heavy.The extra weight doesn't bother me,but I'm a pretty big guy..I also prefer a two stroke because if you blow one up,400 bucks and you are back on the track.Blow up a four stroke,and you are out over a grand,possibly two..I have a YZ450f that I'm riding right now and I must admit that I am almost hooked.They seem to hook up better and turn better,but I'll still be in the 2 stroke cult until they are gone.

 

[IchWarriorMkII]

I find my Wr450f easier to kick start than use the e button.


Go figure.

 

[Timberhauler]

I find my Wr450f easier to kick start than use the e button.


Go figure.

Even after a stall?

 

[IchWarriorMkII]

So far, yeah.

Im sure when the temps starting climbing it might get harder, but thats not been the case so far.