andrewturner
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| posted on 7/11/07 at 11:24 AM |
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4 stroke / 2 stroke
What is the difference between a 4 stroke and a 2 stroke engine and what is the "stroke"?
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Benzine
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| posted on 7/11/07 at 11:28 AM |
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2 stroke vid
This vid explains the 2 stroke pretty well. I want a saab 96 2 stroke 
With a 2 stroke you get good power to weight so you can have a pretty small engine with good power. Need to mix oil in with the fuel aswell.
[Edited on 7/11/07 by Benzine]
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designer
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| posted on 7/11/07 at 11:29 AM |
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4 strokes have cam shafts and valves, 2 strokes do not.
They are much simpler, but don't bother with anything 2 stroke as the EEC are banning them very soon.
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Guinness
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| posted on 7/11/07 at 11:31 AM |
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Wikipedia is your friend.
http://en.wikipedia.org/wiki/Four_stroke
4 Stroke Engine.
http://en.wikipedia.org/wiki/Two_stroke
2 Stroke Engine
HTH
Mike
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nick205
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| posted on 7/11/07 at 12:00 PM |
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And the Wankel engine...
[img][/img]
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mookaloid
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| posted on 7/11/07 at 12:06 PM |
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quote:
Originally posted by nick205
And the Wankel engine...
Image deleted by owner
And how many strokes is that then?
"That thing you're thinking - it wont be that."
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Werner Van Loock
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| posted on 7/11/07 at 12:19 PM |
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quote:
Originally posted by designer
4 strokes have cam shafts and valves, 2 strokes do not.
They are much simpler, but don't bother with anything 2 stroke as the EEC are banning them very soon.
That's not entirely true, most of the 2 strokes don't have camshafts and valves, but there are with valves.
http://www.dieselduck.ca/machinery_page/diesel_engine/diesel_engine.01.htm
http://www.clubstylus.be
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britishtrident
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| posted on 7/11/07 at 01:03 PM |
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quote:
Originally posted by Werner Van Loock
quote:
Originally posted by designer
4 strokes have cam shafts and valves, 2 strokes do not.
They are much simpler, but don't bother with anything 2 stroke as the EEC are banning them very soon.
That's not entirely true, most of the 2 strokes don't have camshafts and valves, but there are with valves.
http://www.dieselduck.ca/machinery_page/diesel_engine/diesel_engine.01.htm
B&W marine slow speed diesel 2 strokes had truly enormous exhaust valves Image from dieselduck.ca
http://www.dieselduck.ca/machinery_page/diesel_engine/diesel_engine.01.htm
 
Rescued attachment modified.ani.sulzer.gif
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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britishtrident
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| posted on 7/11/07 at 01:05 PM |
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In cylinder video
http://video.google.com/videoplay?docid=-5815350492893860613&hl=en
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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coozer
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| posted on 7/11/07 at 01:09 PM |
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2 strokes go 'ring ting ting' and stink.
4 strokes go 'brum brum' and sound crap against a 2 stroke with a 'spanny on
3 moving parts in a 2 stroke, thousands in a 4 stroke.
Mourn the death of 500cc V4 GP bikes
1972 V8 Jago
1980 Z750
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speedyxjs
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| posted on 7/11/07 at 01:37 PM |
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quote:
Originally posted by nick205
And the Wankel engine...
Dont you just love the word Wankel
How long can i resist the temptation to drop a V8 in?
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MikeRJ
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| posted on 7/11/07 at 04:13 PM |
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quote:
Originally posted by designer
They are much simpler, but don't bother with anything 2 stroke as the EEC are banning them very soon.
Going to be a lot of unhappy ship owners then! IIRC the two stroke diesel is the most efficient internal combustion piston engine available.
[Edited on 7/11/07 by MikeRJ]
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nasty-bob
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| posted on 7/11/07 at 06:06 PM |
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quote:
They are much simpler, but don't bother with anything 2 stroke as the EEC are banning them very soon.
Not so sure about that. A few companies, Aprillia for one, are lauching their range of direct injection turbocharged 2 strokes. Beautiful idea. Think
about it- the problems with 2 strokes are lubrication, volumetric efficiency and emissions (due to port timing overlap).
With DI and turbo you can have an oil filled crankcase as per 4 strokes, over 100% volumetric efficiency and as the fuel can be injected after the
scavenging period is complete emissions are up to 4 stroke standards.
So you get all the best bits of a 2 stroke without the bad. Although I will miss the smell......
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Coose
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| posted on 7/11/07 at 11:01 PM |
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You can't beat a good two-stroke (I've had sooooooo many! ).
Did you know, the last of the Honda NSR500 grand prix bikes had been known to put out over 200bhp! They never raced them though as the wouldn't
last a full race....
Yes, that's 500cc, normally aspirated, 200bhp!!!
Spin 'er off Well...
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thomas4age
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| posted on 8/11/07 at 03:38 PM |
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In mc racing if they have a combined field with 2 and 4 stroke engines, almost always the 4 strokes may have about twice the dicplacement against the
2 stroke.
remember that a 2 stroke makes twice the powerpulses per revolution compared to a 4 stroke.
dragracing also used 2 stroke engines with rotating-disk intake and superchargers, those thing made power beyond believe per displacement.
If Lucas made guns, Wars wouldn't start either.
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