^ you need to try out more chambers that work for your kind of porting before you form an opinion about them.

"common RX/2st biker" or not - protons / krp that you get off the shelf are crap IMHO. And even a "common RX/2st biker" who wants to go fast deserves to be pointed in the right direction .

best pipe builders are located in South India. Bangalore , Chennai and Coimbatore are filled with many pipe builders so try and get your pipes off the best pipe builders in one of these cities.

PS: I would also like to add that to see radical gains in power - porting and chamber must go hand in hand . If your going to put on a chamber you might as well give your motor a light port job and get a chamber built accordingly .

Vampire provides sound advice.

Start with the making the exhaust port larger and larger fuel jet (or raise the needle). . The gain you get will be much better than any chamber slapped on a stock bike.

Whatever you decide to so, any changes you make, watch the coloration of your spark plug carefully to see if your engine is running lean or rich. and make adjustments to the fuel. If it runs lean there is a good chance it will seize. Less fuel to the engine also means less oil.