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# In a running engine does the piston ever stop moving?

• Yes
724
• No
203

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In a running engine does the piston ever stop moving?

• 1

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if its off then yyes:smirk:

but no it never stops moving if it did then it would seize..

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Doesn't it stop for a fraction of a second at the top and the bottom of each stroke?

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It physically has to for an instantaneous moment in time in order to change direction .... but only for an instantaneous moment in time..... because for that moment thre would be 0 velocity in the upward or downward direction ...

I think.

heh

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yes it stops at the top and at the bottom simple physic says every thing has to stop before it can change direction

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i hit the wrong button to vote take away one no

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The posts about the piston stopping at the top and bottom of each stroke are correct. So yes the piston stops moving while the engine is running. The connecting rod, however, has a continuous motion.

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well, technically it never STOPS just changes direction. it always has momentum and therefore movement

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In a running engine does the piston ever stop moving?

Ok, you obiviously have a bet going with someone - what's the terms?

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Ok, you obiviously have a bet going with someone - what's the terms?

No bet, just wanted to see what people would say.

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It depends on how accurate you insist on being. The piston does stop upward motion at TDC and downward motion at BDC for a fraction of a second before changing direstions. But during that brief interval it is also bouncing sideways against the bore surface, so technically there is still "motion", even though the piston is not traveling in a linear direction inside the cylinder.

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I guess you could argue that any vibration in the engine, or any movement of the entire engine or vehicle, would mean that the piston is still "moving."

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For the piston to reverse direction is has to come to a complete stop.

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I vote "Yes" also.

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:crazy:Interesting question,,, I've never even thought about that before .

8000 rpm in 60seconds are133.3 per second =266.6 total strokes...

Or would that be 533 on a 4 stroke ?

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Electric engines run and have no pistons. Turbine engines too. Or was the assumption all engines have pistons?

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In my bike the piston is stopped all the time. When it is running, the rest of the universe just bounces up and down...

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This is a cool lil video.

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In my bike the piston is stopped all the time. When it is running, the rest of the universe just bounces up and down...

Heyyyyyyyyyy, is this Chuck Norris?

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Electric engines run and have no pistons. Turbine engines too. Or was the assumption all engines have pistons?

No, but the question was about PISTONS, not different types of propulsion....