If you are asking about disc brake in Gs150 then yes its 100% possible and many have done that before..
It would require 10,000+ rs .
In which you need disc brake assembly, plus new front suspension (used, kabli) of an equivalent Suzuki or China bike.. since these shocks would start to leak under heavy braking of a disc.
Results are only a shashka I think, PBC president has got it installed in Hus bike too... you can ask him for further details.
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