Does 2 stroke engine hold oil?

AndyAndyAndy

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I was looking at some small chinese motorbike today. It had oil drain plug on the bottom of engine. And fill cap with dipstick on the top. Does it 100% mean that it is 4 stroke? (At least that is my understanding - 4 stroke hold an oil and run on fuel. 2 stroke doesn't hold an oil and run on fuel + oil. Right?) Is it in 100% of cases?
 

Kartorbust

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If it has a gearbox integral to the engine, the oil is for the gearbox. 2 strokes mix one of two ways, pre-mix in the gas, or oil injection which will have it's own reservoir.
 

AndyAndyAndy

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How do you tell by cylinder or head?

What about telling by an exhaust? 2 stroke have these weird fat shaped pipes, 4 stroke don't?
 

itsid

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How do you tell by cylinder or head?

What about telling by an exhaust? 2 stroke have these weird fat shaped pipes, 4 stroke don't?

well EASY..

A two stroke has both intake and exhaust on the cylinder walls (intake maybe at the crankcase)
whereas a 4 stroke has both on the head

so finding the seam between head and cylinder and looking
if the intake and exhausts ports are above (4stroke) or below (2stroke)
is all that needs to be done

'sid

PS if it's a motorcycle a two stroke more than likely has an expansion chamber..
but not all do.. thousands of mower engines don't
race kart engines usually don't and worse..
sometimes a two stroke exhaust was mounted to a four stroke engine (for the resonance and mean growl)
Soooo cylinder and head is more telling IMHO
 

Snaker

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Yeah, its not easy to see without getting your fingers dirty, the more panels and clutter, the harder to just "see"
So many different designs.
Like itsid says, the exhaust comes in all kinds of shapes and sizes.

A helpful indicator would be to look at the sparkplug position.
The sparkplug has to go through the head to get to the combustion chamber.

A two stroke: The head is right on top, fairly thin, a bit thicker if liquid cooled.
The sparkplug is exposed right at the top, usually centered but not allways.

A four stroke: The overhead valve body and valve cover sit on top of the head, so the sparkplug tends to be buried down in the valve body or angled in from the side.
 
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