engine help?

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Hey im tip & i live in Philadelphia & i have a 80cc motor... I need some help? I was riding my bike yesterday & out of no where it stop running. i notice when i spin my rear wheel back n forth with the clutch out. i hear noise that sounds like Air coming out from the clutch plate side. plus when i roll the bike with the clutch out, the bike suppose to stop but it keeps rolling & u can hear the engine. my cdi & spark plug is fine, its just i can't keep the bike from moving when the clutch is out. any ideals or videos will help
 
Remove the clutch cover on the right side of the engine. You most likely will need a hand held impact driver to get the screws loose as they are installed very tight at the factory and the screw heads are soft and like to strip out easily.
Take pictures of what you find and post them here if you can.

My best guess is the small pinion gear has come loose on the crankshaft and all heck has gone wrong in there.
 
is there anyway i could post a video or a link to my youtube page. i can show you on my youtube video what im talking about
 
Copy the address of your utube video and paste it in your thread here or there are tutorials that folks have made of how to do it at utube too.
 
Yeah sounds like a serious compression loss. Check Head Nuts first- if loose pull the head and check the gasket
" i hear noise that sounds like Air coming out from the clutch plate side."
Do as Gearnut says, pull clutch cover and check for oil/gas Leaking. If wet at all in there you blew out a case seal.
 
everything eles works fine. its just that one thing in the video thats wrong & i do not where to start. the head nuts are tight in up.. any ideals where to start. and here a picture of what i saw on the clutch cover side
 

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no leak but when it was working when u popped the clutch. there was puff smoke coming out of the 80cc carburetor
 
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spark plug tight? Sounds like it should when no plug in head. compression is def. leaking out of somewhere. Check to see if the gears are meshing and turning correctly behind that clutch cover. Could be your paint job but it looks like an oily engine. Pull all your covers off one at a time and check for oil/air leakage. you gotta narrow it down.
 
ok let me check out & i tight in the spark plug & it still has not change the compression. im gonna check the gears but its sounds like air coming from the cluch gear side when i move my bike with the clutch out.
 
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Pull your covers seems to me you got a seal that blew out. It's happened to me a couple times with a couple diff bikes I had.
 
the air coming from the spark plug. when i petal the bike you can hear a lil bit compression & air leakage coming from where the spark plug goes.
 
the threads is no stripped but im going to tight in it up more to see if its still air leakage. btw let me check i brb
 
I would go but i have a new spark plug already in... i just notice my cylinder head is crack in two. but it still fits on & everything.
 
Your cylinder head is cracked? A crack changes it useful life into a paperweight.
Are you positive that it is not a bit of flashing left behind from the casting process during manufacturing?

If there really is air coming from the clutch area and you have narrowed it down to the clutch/ transmission shaft, that indicates that the crankcase center seam gasket failed in the small area between the flywheel cavity and the transmission shaft cavity.

This requires a total tear down of the engine to replace, so extra caution needs to be taken during diagnosis to be positive that this is actually the problem.
 
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