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No compression after rebuild.

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rawdog

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Discussion starter · #1 ·
Ok so I rebuilt the top end on my ssr 125 sr. Now its worse than before the rebuild.... The reason of the rebuild was because it was smoking alot.
Now I got it back together and go to kick it over and nothing. No popping sound, no exhaust sound, no nothing.... I cant find top dead center using the kicker...

Im really confused and frustrated. Please help I just want this bike to run again...
 
#3 ·
rawdog said:
So i think it has compression because when I turn the flywheel by hand I can feel it hit TDC. I think its a valve timing issue.
Someone please help me!!!
Click to expand...
Do you have the can upside down do you have both the tdc marks lined up on the cam sproket and the flywheel
 
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#5 ·
Cheak that again and someone can help you from here
 
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Discussion starter · #7 ·
When I took the head off the letters lined up to 12 0 clock on the fly wheel. The mark on the cam sprocket was at 3 oclock (not 9)

I think thats part of the issue. I just dont undertand how these engines work so I cant figure out how to resolve it.

When I reisntalled the cam sprocket I installed it I put it back to the 3 oclock posistion
 
#14 · (Edited)
You said you moved it a couple teeth, i thought you were talking about moving the chain. Just follow the rest of the post and you should be good. If you don't have the cam rotated correctly (in the TDC position,) it will still be wrong. When the cam is rotated, you Will feel some resistance. When it is at TDC, there will be a little bit of play back-and-forth. If it is 180° off, you'll notice quite a bit of resistance to turn it there, and it almost feels like it locks in place. Turn the cam till it rotates easily, at that point the "0" should be at 9 o'clock. If it's not at 9, unscrew the sprocket and rotate 180 degrees. My bet is that is what is wrong, as someone else said, the cam is "upside down."
 
#17 ·
rawdog said:
still feels like no compression. I can push the kicker down with my hand..
Click to expand...
There's only A few places where you can lose compression. If you didn't oil the rings up real well, that could be your problem. The head not properly torqued down using a torque wrench, that can cause it. If the valves are set too tight, that can cause a loss of compression as well. Finally, if the spark plug is not in there properly, that can cause a loss of compression. The other thing that can feel like a loss of compression is if your clutch is slipping. Having a higher compression in your engine now because of the rebuild can make that clutch slip.
 
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Maktastik
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