Hello dear, I have a problem with my about 3 years old Nova Motors Retro Star (yes I know the China shit) So far he has done me good service. But for about 1 1/2 weeks he sounds as if there was a hole in the engine or exhaust and does not pull as he should. Instead of 45km/h he achieves a maximum of 35km/h. Today it even happened that he has not accelerated at all and has just drunk off. He jumps on, then chuckles himself also a like a big V8 but he simply does not bring any more performance on the road. Does anyone have an idea? I am a total layman in the field of screwing.. Thank you!