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I cannot remember what model pocket bike this one is, nor is it all that important to me to figure the model of the bike out at this time. However, it was originally a 49cc 2 stroke bike that has since had a 54mm bigbore kit installed, as well as a full circle crank (didn't want to but I had to have a crank with a correctly sized connecting rod bearing hole for the BB kit)a rocket key, and an aftermarket "performance" carb, intake tube and carbon fiber reeds. I accidently overtightened the pinch bolt on the performance carb inlet and broke the inlet off of it. Gotta love cheap cast aluminum... so I bought a similar carb from Amazon that also had a jet kit included. The bike runs SO much better with the correctly jetted Amazon carb, cept that EVERY SINGLE TIME I wide open throttle it, the carb pops off of the intake tube. I cannot figure out how to prevent this from happening and it is driving me insane!
The only possible cause I can figure might be the exhaust system I custom built. The only original exhaust part is the first maybe 8 inches coming off the exhaust port of the engine. The expansion chamber is made from exhaust adapter flanges tapering up to about 2 1/2 and then back down to roughly 1" tubing, which runs into my favorite part of the whole "custom built" system. A gutted spray paint can that I ran the 1" tube through. The pipe inside the spray can exhaust can has a whole crapload of holes neatly drilled through it the entire length of the inside, and the can is packed with exhaust packing. It is held together by a cotter key and a spring. I think it looks pretty fantastic all in all. But I can completely understand the expansion chamber being placed wrong, or incorrectly shaped which wouldn't be any help to the motor, but could it be enough of an issue to cause the dang carb to pop off no matter how snugly it is mounted? I'm afraid to tighten it much more than I have because I really don't want to break another carb needlessly..
I can post pictures of any part of the bike that anyone thinks will be helpful in identifying the cause of this annoying problem.
Thanks in advance guys!
The only possible cause I can figure might be the exhaust system I custom built. The only original exhaust part is the first maybe 8 inches coming off the exhaust port of the engine. The expansion chamber is made from exhaust adapter flanges tapering up to about 2 1/2 and then back down to roughly 1" tubing, which runs into my favorite part of the whole "custom built" system. A gutted spray paint can that I ran the 1" tube through. The pipe inside the spray can exhaust can has a whole crapload of holes neatly drilled through it the entire length of the inside, and the can is packed with exhaust packing. It is held together by a cotter key and a spring. I think it looks pretty fantastic all in all. But I can completely understand the expansion chamber being placed wrong, or incorrectly shaped which wouldn't be any help to the motor, but could it be enough of an issue to cause the dang carb to pop off no matter how snugly it is mounted? I'm afraid to tighten it much more than I have because I really don't want to break another carb needlessly..
I can post pictures of any part of the bike that anyone thinks will be helpful in identifying the cause of this annoying problem.
Thanks in advance guys!