I feel like a frickin moron here...New to two strokes and am trying to figure out how they work...Where does the crankshaft get oil from? Is there a way if it holds oil to check it or change it? Pretty sad when I can build my own car (and I have) and can't work on a damn four wheeler...
Absolute idiot
- Thread starter retrosns
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haha yea i here that lol .. the crank/crank bearings get lubed by the oil in your gas , if u still hve the oil injection the gas will mix with the oil and stuff like that ..
haha its ok i remember asking were to put the motor oil in my snowmobile at and asking if the popping sound was coming from the valves haha.
but to answer your question the gas oil mixture goes from your carb into your crankcase from the vacuum produced by the piston moving up the cylinder and the reeds prevent the mixuture from belting out the carb, all the little oil particles get stuck to the bearings and crank and rod etc for lube i suspect thats the reason why they use roller bearings for the connecting rod dont know about the crank but i asume its the same.
then after floating around in your crankcase for a split second the mixture goes threw a machined hole in the side of your cylinder into the combustion chamber this is caused from the pressure of the piston going down in the cylinder and from the exhaust escaping out the exhaust port.
then the mixture is ignited which forces your piston down and then exits out the exhaust port with it coming "some" unburned fuel from the intake which is the reason why 2 strokes have that expantion chamber "the fat part of the exhaust" the expantion chamber helps redirect some of the unburned fuel back into the cylender.
which is why if you got rid of the expantion chamber your guad would prolly back fire more often from ignitining the unburned fuel in the exhaust.
and the EPA doesnt like that which is why they dont make 2 stroke atv's anymore..........
i hope this cleared up some of your questions
but to answer your question the gas oil mixture goes from your carb into your crankcase from the vacuum produced by the piston moving up the cylinder and the reeds prevent the mixuture from belting out the carb, all the little oil particles get stuck to the bearings and crank and rod etc for lube i suspect thats the reason why they use roller bearings for the connecting rod dont know about the crank but i asume its the same.
then after floating around in your crankcase for a split second the mixture goes threw a machined hole in the side of your cylinder into the combustion chamber this is caused from the pressure of the piston going down in the cylinder and from the exhaust escaping out the exhaust port.
then the mixture is ignited which forces your piston down and then exits out the exhaust port with it coming "some" unburned fuel from the intake which is the reason why 2 strokes have that expantion chamber "the fat part of the exhaust" the expantion chamber helps redirect some of the unburned fuel back into the cylender.
which is why if you got rid of the expantion chamber your guad would prolly back fire more often from ignitining the unburned fuel in the exhaust.
and the EPA doesnt like that which is why they dont make 2 stroke atv's anymore..........
i hope this cleared up some of your questions
=))
Hey dont feel too bad I had the same question I had to tear one apart before I finally figured it out.
Beat me to it Valhalla ! I was just about to find that link myself to post it here... That is a great breakdown of how they work !
There is another good one I was looking for too.
There is another good one I was looking for too.
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I think the back pressure from the expansion chamber creates some kind of sound/exhaust wave that is helping the exhaust escape. Changing the shape, length , or size will change how this works causing it to have power in different times. Thus why different manf. of pipes have different power curves.
oh so thats what the expantion chamber is for i tried explaining the 2 stroke as best as i could i didnt know there was a site haha.
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