My Dear,
Go to any footpath mechanic and get your mehran tuned.
Mehran has got a very very simple and old fashioned engine and there is no tech issue with it.
In mehran there is no booster breaks, no CDI (you will get it in cheap china bikes) no seat belts, busted A/c, rusted doors, and crap of wires.
Better you get rid of it and buy any toyota, mazda and datsun even late 60's model.