Wankel Chainsaw - Why not?

[Luke]

I know Dolmar gave it a try, but in this age of worrying about OPE emissions, (I'm sure they are a significant contributer relative to semi's, jets, and volcano's,,,, sorry) don't they deserve a look. I know Mazda had trouble meeting regs, but I would guess that OPE specs would be easier. Don't know much about them, but are they too expensive to mfg? They would be light, compact, and really spin.

 

[Sprig]

Until they come out with a better, more durable, easier, rotor tip replacement I'd be very suprised to see anyone trying to put them in saws again. Wankle has a great design, smooth, great power to weight ratio and very low vibration, but I think that in small miniaturized versions they just don't cut it; wear 'n' tear, and not great fuel efficiency, possible manufacturing glicks and future support are all probably prohibitive. Just opinions, but I will say that one of the fastest cars I ever rode in was a limited production rally RX2, we hit 140mph passing a wound-out Vette (he beat us dead-rights 60-120 and topped out at 138, he had very big eyes and lots of questions later lol), just a big crazy sewing machine (I believe the block was 115lbs@240+hp, I lifted it out of the car myself when my bud replaced the rotor tips). I read somewhere ages ago that they were designed for running over 20k RPM but its been a while and stand to be corrected. Considering how few parts there are I could see them being cost effective in a car, or bike, but dunno about saws. I think maybe a small turbine would make more sense than one of 'em, and that would be wayyyy fun

opcorn: opcorn:

 

[Ianab]

I can see why you are thinking a Wankel would be good.
Have a look at this little toy
http://www.osengines.com/engines/osmg1400.html

5 cc and 1.27 hp

I guess the problem is that they have to make them Better than a conventional 2 stroke (and not cost any more) before they would take off. And the 2 stroke is pretty well refined technology now.

It would solve the emission issue though, being a 4 stroke and all.

Ian

 

[Woodsrover]

SPECIFICATIONS
Stock Number: OSMG1400
Displacement: 0.303 cu in (5.0 cc)
Practical rpm: 2,500-18,000
Output: 1.27 hp @ 17,000 rpm
Weight: 11.8 oz (335 g)

With specs like that it could run a nice little 10" pruning saw and only weigh a few pounds!!

 

[Ianab]

yeah.. but if you dig a little deeper .

Fuel: Use top quality methanol-based model engine fuel containing approximately 25% castor-oil & between 5% and 15% nitromethane.

I dont think it runs on premium with 50:1 mix
I suspect that running fuel like that it would be a rebuild after each days work too .

Ian

 

[Woodie]

Just opinions, but I will say that one of the fastest cars I ever rode in was a limited production rally RX2, we hit 140mph passing a wound-out Vette (he beat us dead-rights 60-120 and topped out at 138, he had very big eyes and lots of questions later lol), just a big crazy sewing machine

Buddy of mine had an RX2 in high school...what a glorious machine. You're right...think "sewing machine meets rabid river otter on a 3-day meth bender." Those things had to have rev-limiters in 'em cause redline came up so quick, so smooth...this thing just made insane, stupid power, and the car weighed about as much as a 372...less than that if you didn't count the rust. (Of course, you had to count the rust, cause that's really what you had TO count...)

Wankels used to be real tough on seals, although the newish RX8 claims to have a design change that solves that issue. I don't know enough about rotaries to say whether or not it's doable for a saw, but I'd love to see one if it was.

God I miss that car.

 

[Monkeyhanger]

Just opinions, but I will say that one of the fastest cars I ever rode in was a limited production rally RX2, we hit 140mph passing a wound-out Vette (he beat us dead-rights 60-120 and topped out at 138, he had very big eyes and lots of questions later lol

Hi,

I don't find that to be all that fast. My 8 year old 2L 116PS Mitsubishi with 180000km on the clock occasionally managed 220kmh which is about 135mph or so, normally it always managed at least 200kmh/125mph. Do the cars have a speed limiter in them or why are cars that powerul so slow over there.

Not trying to troll or anything, it is honestly a serious question from me.

Bye

 

[Sprig]

Hi,

I don't find that to be all that fast. My 8 year old 2L 116PS Mitsubishi with 180000km on the clock occasionally managed 220kmh which is about 135mph or so, normally it always managed at least 200kmh/125mph. Do the cars have a speed limiter in them or why are cars that powerul so slow over there.

Not trying to troll or anything, it is honestly a serious question from me.

Bye

Heya, fair question with a lot of variables involved.
Lots of stupidly fast cars around, some of the newer ones are rev-limited/governed. In older steel, like the late '50s-'early '70s muscle cars, many were geared for get-up-and-go and lost out on the top-end speed. Nothing like the Auto-baun (sp) around here unfortunately, and no manditory driver's ed. programs, been a lot of carnage over the years on the roads. Some of our shortcomings are; few places to play (street racing is a real deadly problem in some places), people buying their kids fast cars for graduation presents, lack of driving education, and plain ol' lack of common sense (many Darwin Award winners). Just a short note fer the morning.



Serge