Engine rattle/rumble on 2000

[GhostCat]

Hi I met up with a friend who has the exact same bike as me and I was amazed at how much smoother and quieter his engine was, I don't know what to do to mine to make it sound so good. Mine "chugs" a bit on tickover and there is a rattle coming from below the camshaft. The thing is, mines only done 10,000 miles and his has done over 40k. I know my carb rubbers were replaced last year. Regular oil changes etc. Standard exhaust (he has aftermarket sports)
Sorry if this seems a dumb question, hoping someone has had the same problem.

Ghostcat

Mates Fazer: https://youtu.be/9aHeQv3jjEY

My Fazer : https://youtu.be/JLelEU8_MlI