2022. 4. 11. &0183;&32;A lean bog will stop accelerating and sound like the engine is dying; the same equally if you were to hold the kill switch downwardly. A rich bog may allow your cycle to. 2022. 7. 17. 125cc 2 stroke dies when opening throttle When throttle is pulled back from high power, engine stalls rapidly Engine revs and requires brakes to be applied to prevent rapid acceleration A common use for stepper motors is as an idle air control (IAC) valve, which controls engine idle speeds and prevents stalls due to changes in engine load A common use for. Weber bogstoo rich at low rpm. Hi I know this forum might be the best to get answers to this tricky problem I got a 2,2T engine with webers 40idtp3c. The configuration today is Venturies 30. main jet 125. idle jet 60 (even tried .52, .55) The carburetors are balanced and cleaned and float levels correct. If it is way lean on the bottom end, and ragged edge lean on top, the following scenario can happen You go WOT down the straight away. It isn&x27; quite melting, but REAL close. You drop the throttle. The piston has TONS of heat in it, the pipe is hot, now there is no fuel on the underside of the piston to cool it, and the piston melts. To do the rich or lean adjustment, you need to work on the carburetor . Keep the engine running on idle and then take the engine cover off. Locate the carburetor and find the two screws which adjust the fuel and airflow. Adjust each screw according to the best air and fuel ratio for your engine. That was a quick look. Summary. The most likely reason that your two- stroke engine is stalling under load is that your carburetor is dirty or dead. It is still worth it to run through the other, easier fixes of your engine,. Hi, Recently purchased a second hand 50cc Yamaha Jog CV50 (2 stroke) which has done around 11,000kms.. Turn the air screw in to richen the mixture. Back the air screw out to lean the mixture. If your airscrew is on airbox side of carb, turning out will lean mixture. If airscrew is on engine side of carb, it will richen it. Adjusting from 14 to 34 throttle range Raise the needle jet clip to lean the mixture..