I'm pretty sure it would be off going from 25" to 27" but my point was I don't have the hp to hit the limiter with the bigger tires on and I'm pretty sure I didn't gain any top end speed but didn't have a GPS to confirm that. I read on here someone put 27 executioners on and said they hit the limiter at 45. That wasn't the case with me. Could be the difference of a single smaller person vs two ( one very large ) and a cooler. Ill have to put the wife on a diet and try again. Anyone else with 27" or 28" tires hitting the rev limiter?Speedo is now off. Same thing happens when you put bigger tires on a truck.