so basically, I am allowed to go 6-7k rpm easily.... it's just thst I'm feeling engine strain because of comparatively lower torque than the bikes im comparing it with (cb 350 and RE)I am sorry to say but the engine is going to remain the same and things are not going to change dramatically after the first service. This is a hard revving engine and if you want to remain in 3rd gear while doing 50kmph, then you'll be revving the engine past 4-5k rpm and that is when you will feel that the engine is getting strained, which in reality it is not cuz it does come alive at that rpm. But I know what you mean so I would say that you just need to get used to this engine characteristics. From my experience, you will be able to do 30kmph in 3rd gear at roughly 3k rpm and that is when you will feel that the engine is relaxed. Go beyond 3k rpm and you will feel that the engine is stressed. Again, perhaps you feel like that cuz you're used to riding a more relaxed engine.
Thanks for answering btw, i really got perspective