Bent valve 4 stroke motors

Some days my motorcycle sounds strange, but rather like a kind of
buzzing carburetor filter removed. Her voice came from the front
block. Around the ring and piston. Workshop was opened by all major
service, but no matter, piston rings are still intact, I think the
first piston ring broken or cracked or dirty it did not. I let the
motor conditions were ringing for days like this, in his mind because
there is no error, until one day my motorcycle tek tek tek sounds,
sort of impact sound of iron with iron, and direct the motor broke
down, I still can slah but the motor does not want life, I try slah
again, could not dislah alias magak, fortunately this incident took
place near my house, I finally pushed the motorcycle up to the house,
fate. The next day, I called my brother who can fix the machine,
once unloaded, turned the valve hit the piston, fortunately The impact
is not too hard so, the piston is not broken, the valve just a little
crooked, the brothers finally straightened out again and the valve can
be refitted, be advised to buy valve is not enough money. Once I
remember, it was ringing but the engine noise sounds like a carburetor
removed, it comes from the valve began to bend, resulting in the valve
can not close perfectly, tenagapun feels sluggish, its top bent
valves, umbrella valves hit the piston, and the engine lost
compression resulting not turn