Exhaust makes loud pop/bang after piston change and setting cam timing.

[hussainfast48]

I got a stomp juicebox 3 110cc off my friend. He told me he was riding it and the bike slowed down and when he turned it off it wouldn't turn back on. I knew a bit about bikes and after searching forums and watching youtube videos I figured out it was the piston ring were worn. I then asked and actual mechanic and told me the same thing. After changing the piston it had a lot of compression but still wouldn't turn on. I then figured out the cam timing were wrong after fixing this the bike had less compression when you kicked it but still had some. After kicking it a bit with the choke up it made a loud bang/pop like a gun. Kept on kicking then there was another bang. when i tried bump starting it made a loud bang again. The second time I bump started it sounded like the bike turn on for a second but then turned off. Now when i try starting it nothing it wont make a sound or bang at all. Also there is alot of oil leaking from the cylinder i need to get gasket maker but I did put a new gasket.

 

[Darwin]

If timing is off the valves are going to be opening/closing at the wrong time. That could explain the low compression problem. Need to get the timing correct then you can see where your at.

 

[hussainfast48]

If timing is off the valves are going to be opening/closing at the wrong time. That could explain the low compression problem. Need to get the timing correct then you can see where your at.

the timing is correct im pretty sure. if you want i can send a picture of it

 

[Motley]

That almost sounds like an EGR/PAIR valve cover setup with an aftermarket exhaust problem.

I can't find anything valve cover related for your motor so it's hard to say. But if you do happen to have this setup, I would suggest sticking a bolt in the hole for a quick test. If there is no longer any blow back they you need to get a non emission cover, or get ingenious. You could gain more compression by patching it..

As you said a gasket maker, if you have a oil leak then that's your problem. But firstly...

Did you look up the specs on the amount of torque you are suppose to apply?
Do that before trying to bypass anything firstly. That might be enough to fix everything...

I hope your problem is fixed by now

 

[hussainfast48]

That almost sounds like an EGR/PAIR valve cover setup with an aftermarket exhaust problem.

I can't find anything valve cover related for your motor so it's hard to say. But if you do happen to have this setup, I would suggest sticking a bolt in the hole for a quick test. If there is no longer any blow back they you need to get a non emission cover, or get ingenious. You could gain more compression by patching it..

As you said a gasket maker, if you have a oil leak then that's your problem. But firstly...

Did you look up the specs on the amount of torque you are suppose to apply?
Do that before trying to bypass anything firstly. That might be enough to fix everything...

I hope your problem is fixed by now

it doesn't make a loud bang anymore it doesnt turn on at all. when i bump start it starts for a 30 seconds but there is no rev as long as the bike is moving the bike doesn't turn off.