The only way to increase the power of the Hero Honda CD100 is by changing the piston of the engine and replacing them with a bigger one with a bigger bore value. This will increase the power but would result into lower fuel economy and the engine stability will also be effected. Its better to leave the engine as such as it may create further problems in the bike.

Yup, u can buddy, just u need to alter few things to make ur bike faster, u can use KNN filter to make it fast.