Itna tu bike ko wesay he kerna chahye ager itna bhi nahi ker rahi tu it has some problem..
Get ur self a good mechnic who can Diagnose it right.
If I were you what I would do #
1 - Get Plug Color Checked, try out on different feul settings, Some times we are running to rich just to gaiun speed and no having good combustion
2 - Free the Air Flow (Exhust and Filter), Align the wheels Good Air pressure in tires.
3 - Use Good Petrol dont go pure Hi Octane but use 1/3 in ur total Feul to have good feul our "regular" feul is just another variant of mitti ka tail (sarcasmic) ruining our bikes..
I will get this done after finding a good "CG racer mechnic" who has spent time on racing and know what you are looking for... and guide him and listen to him what he says..
Is tran k masla 'One go' men hal nahi hotay .. bara time or fortune ligana perta hai..
but in your case I can assure you bike should go to 120 or some where near to 120 like 115kmh without any alterations and just tuning it properly..
I remember My Stock CG125 2008 was all stock not tuned by any racer was able to hit above +110kmh any time after two years when I switched to 2010 new Model it never even crossed 105kmh even.. 6 months men he dispooint ho ker sale ker diya tha
I hope this helps.
Regards.