Just alittle should not be that bad.
no
Under the carburetor.
backfire timing off
The intake valves are bigger, and lead to the carburetor. the exhaust valves are smaller and lead to the manifolds or headers.
Regulate the carburetor and replace its gasket.
Without the exhaust back pressure, the engine could run a little richer. You may need to readjust the carbs to get the bike to run smoother.
29 -35 mph with the right exhaust. That is possible with even a restrictive exhaust and small carburetor, as set up for child drivers. A larger carburetor and more open exhaust system will allow for speeds exceeding 70 mph, particularly when coupled with aerodynamic chassis types.
a flooded carburetor will spill fuel into the combustion chamber causing an improper fuel to air mixture. too much fuel in the combustion chamber will not completely burn. the unburned fuel will be pushed out of the exhaust.
All carburetors need to be free of buildup or debris so that they can omit exhaust. The exhaust system on a Mazda 323 can be serviced by a mechanic.
The intake manifold distributes the air fuel mixture from the carburetor to the cylinders. The exhaust manifold collects the exhaust gases from the cylinders and directs them out the exhaust pipe.
check the exhaust and google 'restriction' The restriction plate is in between the carburetor and the air intake
Automobiles release exhaust. These exhaust gases deplete ozone.