125 what is the reason why the throttle of motorcycle can't be reset automatically?

125 The throttle of motorcycle cannot be reset automatically. The fault is caused by the throttle pipe and throttle handle. Check whether the carburetor is improperly installed, causing the throttle valve to be too tight in the carburetor. After some inferior carburetors tighten the mounting screws, the throttle will not come down. Check whether the throttle valve does not return due to the influence of engine heat on carburetor, and install heat insulation pad if necessary. Check whether there is a problem with the installation angle of carburetor, which causes the throttle pipe to be stuck after installation.