Query Approved.

I would think it could be because of lean mixture. Check the carb settings. SVC tends to keep the setting to lean for mileage, however, in the longer run tends to develop issues. This is one of them.

My bike has run 45k and have not changed bore till date from 2005. Since you have changed the bore, should not run lean and need to keep the RPM mellowed while riding.

You will need to check with SVC to check if the carb is tuned just right(not too lean nor rich). Infact ask them to completely clean the carb.

Let me know on this.

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