I need help piston hitting head!!!

jld0619

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So I had to get a new cylinder for my motorized bike because the exhaust manifold f***** up, so I ordered a new cylinder and piston kit off Amazon. I've got it installed but for some reason the Piston is hitting the head. Can someone please help me?
 

jld0619

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This is the one that I ordered and this is the old one
 

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DAMIEN1307

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Does the wrist pin hole measure the same to the top of the piston?
You need to take it apart and compare the two pistons very carefully then.
Also, is it a flat top, dome top, or "pop" top style piston???...Is the old piston it replaced also identical???...There has to be some obvious difference here.
 

FrizzleFried

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This is the one that I ordered and this is the old one
You can very plainly see comparing those photos that the "hole" on the piston is in two different locations (actually, it looks like one piston is simply "taller" than the other with more room at top ... which explains why you're hitting the top of your head..
 

DAMIEN1307

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You have a low hole piston on a high hole piston rod, from your pictures you can see there is a lot more piston above the hole on the new compared to the old.
You can very plainly see comparing those photos that the "hole" on the piston is in two different locations.
I'm glad you guys could tell that from the pics...lol...One from an ad and the old one in hand...lol...I certainly could not "see" a difference, I would go by measurement rather than rely on that generic pic from the ad...In other words, both "real" pistons side by side with all points and measurements being taken into consideration.
 

DAMIEN1307

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I work in graphic arts. It's PLAINLY obvious there is more space from the hole to the top of the piston on the left (to me).
The only thing I can see for sure in that artists illustration is that the skirting appears to be shorter in the first pic than the one he is holding in hand...lol...I never trust artist conceptions in illustrations to be actual reality...lol.
 

FrizzleFried

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Naw... it's very obvious there is more space between the hole and the bottom ring with the one on the left. Again... to me.

That said, I do suffer from OCD to some extent (which helps me in my work but don't EVER hang pictures with me!).
 
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