Royal Enfield — classic 350 engine noise

I have started using bike from 2015. It's almost 4 years bike. I did service as per schedule at re authorized center only. Daily usage of my bike is less than 25kms. From day 1, i have noticed engine sound and complained with re mechanic in chennai/bangalore & anantapur also but they used to say that no problem. From past 1 month engine sound become more so i gave in service center. Now they are saying that engine problem need to replace some parts. It will cost around 15/20k. I just shocked by hearing that number.

It's very pathetic. Worst engines from re.