Yz80 case oil

i have recently gotten a 2000 yz80 and i went to the local bike shop to get some parts. the kid behind the counter said i would need case oil and to fill it til i saw the oil. i did that and the bike ran good for about 2 hours and then it shut off. well in the past 3 weeks i have been working on the bike and i went to go get the bike shop to pay for the parts. well they were sayin that the case doesnt compress which is wat blew out the gaskets. so does the case compress or doesnt it i need some help.:busted:

Um...you don't fill until you see it.You can remove the check plug and fill it until it runs out of this-failing that,the capacity should be stamped on the case near the fill plug.It just lubes the clutch and transmission-nothing else.:busted:

but does the case compress???

as you can see i am a newb to the two stroke.

at the bike shop they are telling me it doesnt and the

mechanic is telling me it does and thats why it blew out the gaskets and seals in the bottom end.

Somebody in this loop is running on a bent crankshaft. The gear box oil is put in as a measured amount usually around 500cc. If you filled it untill you saw it I'm betting you were at least 250cc over full. No telling how much damage was done depending on the state of the vents and such

we checked it out but everything was fine.

its just the time and cost to split the case

and the repair shop that caused it is argueing with us.

it blew out all the seals in the bottom end.

wouldnt that be because the case compressed?

i was told that is how the two stroke gets its power

but im not sure

I'm not even understanding the terminology that the case compresses. No the case does not compress. The case fills with intake charge and is drawn into the cylinder. Face it you screwed up and put in to much oil it had to go somewhere and it pushed the seals out

nevermind i understand now but thanks for being so patient

You have two different compartments in your case. The transmission, clutch is separate from the crankcase. You do need to put oil in the transmission/clutch. You do not put oil in the crankcase. You bike sucks the gas/oil/air mix through the carb, through the reeds and into the crankcase when the piston goes up. Then when the piston comes down it compresses the gas/oil/air mixture until the intake port is uncovered letting the now compressed mixture flow into the combustion chamber.

If for some reason the crankcase was full of oil the reduced area in the crankcase could lead to excesive pressure and blow out the seals. I'm not sure how you would manage to put oil in the crankcase, though.

I wouldn't think that adding too much oil to the transmission would blow out "all the seals" most likely you would have an oily mess draining out of the tranny breather line.

thanks everyone

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