I don't have an R, but everyone seems to agree that if you only drill holes you do not need a tuner on these engines. If you drill holes AND mod the intake, such has high flow filter and or topless, you will need a tuner.
i drilled 6x1/2" holes on my "R"... gave a nicer tone but still 2 quiet.4me..i did about8k miles like that and never had it re tuned...
I then went the next step and ran a 3" hole saw and pulled the whole baffle out..SOUNDS GREAT !!!, but is "very" loud, gives a very nice deep throaty tone now.(think the hollow mufflers are acting like a megafone)..All the lads say how great it sounds. Only prob is the ears are ringing 4 about 10mins after stopping the bike :-0.
As 4 re-tuning i had done about 5k miles with no baffles b4 dynoing (only dynoed because i add the Boss Noss system) and they told me it had been on the lean side jst a little, but wasn't that bad that it would hav hurt it. Now the Nos has been added they retuned it with the computer that came with it.
Hope that helps