woodsguy
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True?
- Thread starter woodsguy
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woodsguy
Ride Red
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Wouldn't even try
dukey33
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Why is it not 100% more since it makes power on every down stroke and doesn't have all the internal losses associated with a valvetrain?
50% more suggests each power stroke is 25% less efficient than the power stroke in a 4-stroke. Is that true?
edited to correct for lack of coffee
50% more suggests each power stroke is 25% less efficient than the power stroke in a 4-stroke. Is that true?
edited to correct for lack of coffee
Last edited:
garfey
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Well there is a lot of variables that come into play. The main thing is efficiency of a 2 -stroke is reduced since it uses ports instead of valves to control intake and exhaust timing. They lose part of the air fuel charge every cycle. 4-strokes also lose some some air fuel charge, just not as much. On the 2-stroke port height in the cylinder and relation to one another change efficiency and power delivery. 4-stroke efficiency is effected by cam timing, lift and duration as well as other factors like length of crankshaft stroke and rod length, also where the rod is connected to the piston determines how long the piston is at TDC. Then you can get into static vs dynamic calculations. Blah...Blah...Blah...
So while the statement in the meme is somewhat correct to say that an equal displacement 2-stroke is more powerful than the 4-stroke you can't make a blanket statement about a percentage. You could also look at the fuel consumed to make the extra power and then draw some conclusions about overall efficiency of out per BTU of fuel consumed to make the power.
P.S. I'm not an engineer or certified in anything nor do I play one on TV so if someone wants to add to or take away or otherwise educate us please chime in.
So while the statement in the meme is somewhat correct to say that an equal displacement 2-stroke is more powerful than the 4-stroke you can't make a blanket statement about a percentage. You could also look at the fuel consumed to make the extra power and then draw some conclusions about overall efficiency of out per BTU of fuel consumed to make the power.
P.S. I'm not an engineer or certified in anything nor do I play one on TV so if someone wants to add to or take away or otherwise educate us please chime in.
No scientific or mechanical evidence but on the last 2 stroke I rode I saw 50% more skyward views. At least that's the direction the front wheel was pointed most of the time. I must admit the ability to loft the front whenever you please is very addictive. 