Re: 4.0 hp high rpm problem
theres really not much to learn from shutting off the gas supply and being able to rev it up just before it runs out of gas, this "high rev" when running out of gas is typical of a two-stroke engine...the pistons do not have to compress as much fuel vapor...it might let the motor rev high, but it will not make much power when "leaning" the fuel supply out. in my experience "Bogging out" is generally a fuel supply issue (lack of fuel). you might want to check your timing and carb synchronization...the distributor timing has to be right with the carb throttle plate opening position to burn this added fuel, if the spark timing and fuel delivery rate are not in sync, this could create loss of top end RPM's (no timing advance) and bogging from not igniting the fuel at the correct time. very few motors "bog" from excess fuel, especially trying to achieve high RPM's, low RPM flooding, quite possible...high RPM bogging or flooding from gas...doubtful. just wondering about the timing? LOSS of top-end power = poor compression, insufficient fuel supply or no timing advance.
