Ok guys need your help.
First, my bike: 1998 Gsxr-750. All stock but with Micron slip-on. However I do have a TRE installed.
Type of rider I am: Well I am 43 yrs old. I ride my Gsxr like one would ride a Harley

..meaning I dont ride hard too often.
Problem: The other day me and a friend was hanging out one night. BTW he has a '02 Busa. We hit a stretch of highway that was wide open. So we decided to push it a little. We were neck and neck doing about 110mph. Then of course he left me like I was moving backwards. I figured that would happen but here is the problem. When I "tried" to catch up I was at full throttle doing about 112-115mph at about 8000 rpms (I think, I was trying to keep my eyes on the road and not the readouts). It seemed I could not go any faster. But I thought my bike would at least get 135 or so. My friend said that I should have dropped down into 5th got my rpms up to almost read line
and then hit 6th. I am not a "racer" per se. This is where I need your help.
Question: Is it rider skill or do I need a remapping. I bought the bike used from a friend that buys at auctions. I have not done anything to it that affects performance other than the TRE. What do you guys think?