dumb question but

BobbyM
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BobbyM
Edited Date/Time 6/1/2013 9:48am
CC FOR CC what engine would make the most power...a 2 stroke or a 4 stroke. no limits on the mods.
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MXR
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MXR 5/31/2013 6:09pm
5/31/2013 6:09pm
The 500
braap981
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braap981 5/31/2013 6:14pm
5/31/2013 6:14pm
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but 2 strokes in my opinion make you a better rider!
WhKnuckle
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WhKnuckle 5/31/2013 6:22pm
5/31/2013 6:22pm
Two stroke, no doubt about it. Twice as many power strokes per revolution means a four stroke would have to be twice as efficient as the two stroke to make the same power. Nobody can make an engine twice as efficient no matter what they do.
RM127
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RM127 5/31/2013 6:31pm
5/31/2013 6:31pm
braap981 wrote:
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but...
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but 2 strokes in my opinion make you a better rider!
Look at the torque rating on a 250 2t, it smokes 250 4t's!

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WhKnuckle
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WhKnuckle 5/31/2013 6:36pm
5/31/2013 6:36pm
Maybe somebody will invent a one stroke.
Outsider
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Outsider 5/31/2013 6:49pm
5/31/2013 6:49pm
WhKnuckle wrote:
Maybe somebody will invent a one stroke.
Uh, I invented that in high school.... Blush
Kryan5
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Kryan5 5/31/2013 6:57pm
5/31/2013 6:57pm
WhKnuckle wrote:
Maybe somebody will invent a one stroke.
Outsider wrote:
Uh, I invented that in high school.... Blush
Haha. You won the internet today. Pure gold!
braap981
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braap981 5/31/2013 6:58pm
5/31/2013 6:58pm Edited Date/Time 5/31/2013 6:59pm
braap981 wrote:
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but...
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but 2 strokes in my opinion make you a better rider!
RM127 wrote:
Look at the torque rating on a 250 2t, it smokes 250 4t's!
125's are the equivalence to the 250 four strokes, 250 two strokes are the equivalence to the 450 so if you put it that way the 125 and 250 two strokes doesn't have the torque but it's got the power and top end to make up for it, it just all depends on how you look at it
WhKnuckle
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WhKnuckle 5/31/2013 7:03pm
5/31/2013 7:03pm
WhKnuckle wrote:
Maybe somebody will invent a one stroke.
Outsider wrote:
Uh, I invented that in high school.... Blush
It's not the number of strokes, it's the strength of the combustion.
Outsider
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Outsider 5/31/2013 7:07pm
5/31/2013 7:07pm
WhKnuckle wrote:
Maybe somebody will invent a one stroke.
Outsider wrote:
Uh, I invented that in high school.... Blush
WhKnuckle wrote:
It's not the number of strokes, it's the strength of the combustion.
If I remember correctly, it blew the head gasket, snapped the rod, and spun a crank bearing!!!Woohoo
burn1986
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burn1986 5/31/2013 7:12pm
5/31/2013 7:12pm
Why?
WhKnuckle
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WhKnuckle 5/31/2013 7:15pm
5/31/2013 7:15pm
Outsider wrote:
Uh, I invented that in high school.... Blush
WhKnuckle wrote:
It's not the number of strokes, it's the strength of the combustion.
Outsider wrote:
If I remember correctly, it blew the head gasket, snapped the rod, and spun a crank bearing!!!Woohoo
When you get into your late 50s, you'll find that you don't have quite as much compression as you used to. Rev up is a little lazier, top rev limits are lower, balance is a little off and the exhaust gets pretty smelly. But you can still get things running most of the time.
MX7MX
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MX7MX 5/31/2013 8:01pm
5/31/2013 8:01pm
WhKnuckle wrote:
Two stroke, no doubt about it. Twice as many power strokes per revolution means a four stroke would have to be twice as efficient as the...
Two stroke, no doubt about it. Twice as many power strokes per revolution means a four stroke would have to be twice as efficient as the two stroke to make the same power. Nobody can make an engine twice as efficient no matter what they do.
I beg to damn differ! Throw a little boost at an engine and see what happens!
bullpen658
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bullpen658 5/31/2013 8:08pm
5/31/2013 8:08pm
WhKnuckle wrote:
Maybe somebody will invent a one stroke.
Outsider wrote:
Uh, I invented that in high school.... Blush
Kryan5 wrote:
Haha. You won the internet today. Pure gold!
I agree. Internet champion.
Derpin' DJ
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Derpin' DJ 5/31/2013 8:14pm
5/31/2013 8:14pm
WhKnuckle wrote:
Maybe somebody will invent a one stroke.
I guess you could consider this a one stroke

gotwings
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gotwings 5/31/2013 8:56pm
5/31/2013 8:56pm
Suzuki rotary. 0 stroke.
TerryK
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TerryK 5/31/2013 9:06pm
5/31/2013 9:06pm
braap981 wrote:
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but...
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but 2 strokes in my opinion make you a better rider!
I don't understand why so many people think a modern four stroke makes more low end torque and power than a two stroke. To make lots of power out of a small displacement 4 stroke you have to spin it at high rpms. Most 450s rev over 13000. A 250 two stroke revs to around 8000 rpm.

Look at the torque specs of both and you'll see it plain as day.
twosmoke30 5/31/2013 9:29pm
5/31/2013 9:29pm
braap981 wrote:
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but...
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but 2 strokes in my opinion make you a better rider!
whoa whoa whoa.....cc for cc a 4 stroke can't touch a 2 stroke in torque, bottom end, snap, top end, over rev

you're thinking of 250 vs 450 or 125 vs 250f..

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JB 19
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JB 19 5/31/2013 9:53pm
5/31/2013 9:53pm
I would be curious if you included F1 4 stroke technology and Grand Prix 2 stroke technology. You might be surprised. Honda was fairly close in the 80's in 500 Grand Prix racing with their 4 stroke vs the 2 strokes.
burn1986
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burn1986 5/31/2013 10:01pm
5/31/2013 10:01pm
Who cares? This thread is only a troll thread by BobbyM. Stupid
BobbyM
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BobbyM 5/31/2013 10:06pm
5/31/2013 10:06pm
burn1986 wrote:
Who cares? This thread is only a troll thread by BobbyM. Stupid
fuck off...

now back to the subject matter. is there documentation that shows head to head the difference in HP output?

test...mxa...popular mechanics...popular science...highlights? anything.....?
burn1986
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burn1986 5/31/2013 10:11pm
5/31/2013 10:11pm Edited Date/Time 5/31/2013 10:20pm
How long have you been on motorcycles? A long time. We all have you know as much about this as we all do, so why ask? The real question is "how do you get the promoters to have some balls and allow the displacements of 2s to be increased?

A fully modified 2-stroke would includes flywheel weight and would pull greater than a 4-stroke of the same size.

The 2-stroke will soon be prohibited in AMA racing so it won't matter.

Whatever, continue on.
jeffro503
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jeffro503 5/31/2013 10:57pm
5/31/2013 10:57pm
WhKnuckle wrote:
Two stroke, no doubt about it. Twice as many power strokes per revolution means a four stroke would have to be twice as efficient as the...
Two stroke, no doubt about it. Twice as many power strokes per revolution means a four stroke would have to be twice as efficient as the two stroke to make the same power. Nobody can make an engine twice as efficient no matter what they do.
MX7MX wrote:
I beg to damn differ! Throw a little boost at an engine and see what happens!
What? Are you saying that you can squeeze out more ponies out of a 250F than a 250 2 stroke? Just want to make sure this is what you are saying.
ando
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ando 5/31/2013 11:21pm
5/31/2013 11:21pm
If it's just power then possibly a four stroke could be made with a very short stroke and high rpm that could make more power. Torque would sacrificed however so it might not be an ideal MX engine.
BobbyM
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BobbyM 5/31/2013 11:42pm
5/31/2013 11:42pm
serious question...debating with a dude from work.
ToolMaker 6/1/2013 7:01am
6/1/2013 7:01am
No limits on the mods? Are we talking at a specific rpm, rideable power? Single cyl, multiple cyls? 4 stroke with Coates spherical valve technology.
TM
SouthwestMfg
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SouthwestMfg 6/1/2013 9:25am
6/1/2013 9:25am Edited Date/Time 6/1/2013 9:26am
Assuming you are limiting this to internal combustion piston engines. Equal displacement should be able to produce equal energy. Throwing that one out there for Steve Bruhn’s memory - because it physics.

For MX bench racing purposes, it's great topic, that will never be settled. Bobby I know you rode the "mighty-Maic's" (Allen Berteluti expression) so you know the two stroke can be tractable power wise, maybe you rode a modern four-stroke. What’s you opinion?.

As far as ultimate power your limit is always physics . . Not a dumb question, it's why there's still a lot of people working endlessly to "make em scoot ! ! " better thant the next guy.
BobbyM
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BobbyM 6/1/2013 9:45am
6/1/2013 9:45am
SouthwestMfg wrote:
Assuming you are limiting this to internal combustion piston engines. Equal displacement should be able to produce equal energy. Throwing that one out there for Steve...
Assuming you are limiting this to internal combustion piston engines. Equal displacement should be able to produce equal energy. Throwing that one out there for Steve Bruhn’s memory - because it physics.

For MX bench racing purposes, it's great topic, that will never be settled. Bobby I know you rode the "mighty-Maic's" (Allen Berteluti expression) so you know the two stroke can be tractable power wise, maybe you rode a modern four-stroke. What’s you opinion?.

As far as ultimate power your limit is always physics . . Not a dumb question, it's why there's still a lot of people working endlessly to "make em scoot ! ! " better thant the next guy.
I raced moates FMF yz 450 a few years back and I saw more blue sky than track. It seemed to have as much get up and go as my stock kx500. I sometimes wonder if one of the big four... or five made a 500 rotary valve engine for purchase...if it could blow away a modern day pumped up 4stroke.
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Katoomey 6/1/2013 9:48am
6/1/2013 9:48am Edited Date/Time 6/1/2013 9:55am
braap981 wrote:
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but...
2 stroke makes more power than the 4 stroke, but the four stroke makes more torque and bottom end power they're also easier to ride but 2 strokes in my opinion make you a better rider!
TerryK wrote:
I don't understand why so many people think a modern four stroke makes more low end torque and power than a two stroke. To make lots...
I don't understand why so many people think a modern four stroke makes more low end torque and power than a two stroke. To make lots of power out of a small displacement 4 stroke you have to spin it at high rpms. Most 450s rev over 13000. A 250 two stroke revs to around 8000 rpm.

Look at the torque specs of both and you'll see it plain as day.
a fourstroke has a larger spread of power. This makes people think they have more torque, and for all intensive purposes, they do have more usable torque.

with a 2 stroke you cant really have both top end power and low end grunt. 4 strokes can to some degree.



to anwser the OP's question though, I don't think 9,000 horsepower is possible with 572 cubic inches of 2 stroke - especially not one that was as compact as a 572 V8. we can't forget architecture (type, shape, and dimension) here people. it isn't just cc size vs cc size. you have to look at the entire power package to relatively compare something. especially cylinder count.

a CR 500 makes about 110-120 hp per liter.
CBR1000 makes a 165 hp per liter.
A (Suzuki) snowmobile engine (twin smoker, 800cc) makes about 200 hp per liter.
moto gp 500cc smoker of yesteryear = 320-350 hp per liter
moto gp bike of today (800-1000cc) = 220-240 hp per liter


my point is that by and large 2 strokes are regularly superior in peak horsepower, but not always, and that the architecture plays a major role in power production among internal combustion engines.

I love smokers, but they have their place, and that place is getting smaller and smaller all the time. 4 strokes just offer more usable power spread. Thats the greatest asset a motor can have.

i will probably never own a 4 stroke motocross bike, but I'm not a big enough idiot to say that 2-strokes are better for the job of motocross. they are not.


if you put 250 smokers in the lites class I don't think they would have much of an advantage if any, and no 300cc smoker is going to out pace a 450. I have 2 300cc smokers, and yeah they work marvelously off-road, but they are ducks on an mx track. ...and my 300's are tuned and ported for full on mx power, not the chug-a-lug power they had stock.

you cannot underestimate the traction advantage a four stroke has. it's that simple

Post a reply to: dumb question but