I have also used Grip Puppies in the past, and as mentioned they do make the grips quite large(and as a side note also take longer for the heat of the heated grips to come through and IMHO limit the heat somewhat). The past few bikes I have installed Gel grips(replacing the OEM rubber). Size wise they sit between the OEM and Grip Puppies, they allow full heat and work a little towards vibes(but a word f warning, the throttle side rubber is a bitch to get off).