Paid 270 for the plug.
I think it's better to change the plug after 10k km, no matter how the condition is. Suzuki manual calls for plug change every 9000Km i think.
My bro was complaining of decreased pick, increased fuel consumption and patakhas in his Junoon. He never changed the plug and plug had over 15K km on it. When i checked it, its cathode tip was partially eaten from one side and it was black showing signs of incomplete combustion. I immediately replaced it and told him to get it replaced every 10K km.
But which model is that?
I bought NGK C7HSA for Junoon which costed 170. While GS spark plug was for 270.