Won't start

Whitewill1412

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I just built a 2 stroke 66cc bike. At first had no spark and replaced the cdi coil. Now I have spark and it still won't start. I just took the carb all apart and everything looks good. It has compression. Seems like it's not getting gas, but I can't see why. Does anyone have any ideas what could be wrong?
 

Whitewill1412

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I just noticed the arrow on top of the piston. I can see it through the spark plug hole. The arrow is pointing toward the intake. Is it backwards? If it is backwards would it not start?
 

DAMIEN1307

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I just noticed the arrow on top of the piston. I can see it through the spark plug hole. The arrow is pointing toward the intake. Is it backwards? If it is backwards would it not start?
That would depend...I have seen pistons with the arrow on the wrong side of the piston...Here is how you can tell.

The arrow should face the exhaust port ONLY IF the ring pins, (those are the little pins that the open ends of the rings press up against when you put the rings on the piston), Are facing the INTAKE side of the piston.

In any event, you will have to remove the cylinder jug off of the lower part of the motor and check for sure that the arrow faces the EXHAUST, and the ring pins face the INTAKE...No matter which way the arrow is, the ring pins MUST be facing the intake port side...Take care that the rings are put on in such a way that when putting it all back together, that the rings are NOT over the pins, but that both ends of the rings have the pin in between them.

We can proceed to the starting issue once we are sure the piston is in correctly.
 

Whitewill1412

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That would depend...I have seen pistons with the arrow on the wrong side of the piston...Here is how you can tell.

The arrow should face the exhaust port ONLY IF the ring pins, (those are the little pins that the open ends of the rings press up against when you put the rings on the piston), Are facing the INTAKE side of the piston.

In any event, you will have to remove the cylinder jug off of the lower part of the motor and check for sure that the arrow faces the EXHAUST, and the ring pins face the INTAKE...No matter which way the arrow is, the ring pins MUST be facing the intake port side...Take care that the rings are put on in such a way that when putting it all back together, that the rings are NOT over the pins, but that both ends of the rings have the pin in between them.

We can proceed to the starting issue once we are sure the piston is in correctly.
Thanks for the reply. I am going to take it apart as you said. Have to go to the store and make dinner right now, but I will get to it soon
 

Axl Myk

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Pull the piston. When putting it back in, use one of these to compress the rings.
 

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DAMIEN1307

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Next thing then...Do you know where you positioned the C clip on the needle valve that controls your float level on the carburetor???
 
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