i'm not sure you need to have them reground. Instead i would ask to have them re-lapped. That means they put a mildly abrasive agent on the valve seat, and using the valve itself, they rotate the valve face around on the seat, this creats a good sealing surface between the valve itself and the seat. Not something i would do yourself if you do not have experience, but if you know someone who does and is willing to helo ya, it's not that difficult.
Re-cutting the valve seats can be fairly expensive on an R1, as there are 20 of them to do:crash