its not a myth Amjad.. its just a misunderstanding of local riders... even a OHC CD70 vibrates lit a drill machine after 75KMH speed.. so its a lame point ... the limitatation is that OHVs face power loss after there peak power RPms which is 10/11k RPM in bikes ... where as OHCs can go ahead ...
CG125 faces vibration becuase it is a bike from those decades when vibrations were not considered an issue, paiggio is todays bike and adresses it properly ...
there is a reason why paiggio being chinese stayed and turn out strong and other chinese 125's are resting in peice at mechnics shops .. becuase it does have many latest engineering marvels which still are still missing in all japs (local) bikes uptill now and which were never dreamt by any Pakistani riders before but I didnt bothered to tell them again and again .. .. ..