im no expert when it comes to NSRs (thats way im on here to learn) other than knowing there a right laugh to ride
but 13,000 rpm ,that can be doing it anygood
take mine to about 11,200 then its time for another gear ,if theres no gears left ,then just tuck in and smile
as for as my 21 goes theres no point in reving it above 11,500