I've found some other forum posts about this issue and have done some research, but the posts seem pretty old and I'm going to post this thread to see if anyone out there has diagnosed and hopefully fixed a similar issue as of recently. I have an all-stock (except slip-on exhaust) 2005 CBR600rr with a little over 22,000 miles on it.

For the past month, I have been experiencing what I would call RPM hesitation. After about 12,500 RPMs in 4th, 5th, and 6th gear, this happens and the bike stops pulling. It basically feels like a stall in power. Even though there is more twist in the throttle, it doesn't pull any farther. It makes a slight bogging sound. Sometimes you can work your way past it if you are trying to pull past it long enough and not too quickly, but its almost impossible to get past 13k rpms in 4th gear and above now. In 1st and 2nd gear, it seems to rev past 13k rpms just fine which is weird. My mechanic told me to try gasoline cleaner additive and use the ethanol-free 91 gasoline at a gas station near me to see if it cleans out some fuel components, but I have been doing this and the issue hasn't been resolved.

This wasn't happening when I first bought the bike. I do drive this bike in top speed range a lot on the highway (in Mexico) for extended periods of time. There were a few occasions before this issue started happening, where I was driving close to my redline (15k rpms) in 6th gear on 40-minute highway drives for most of the drive. Could this be caused by beating the **** out of the bike too much? Driving close to redline (14,600 rpms in 6th gear) for too long?

On previous posts I found on google, I saw people mention a potential spark plug issue, but others disputed that idea. Some mentioned it could be a fuel system issue, and maybe I need to replace some components like injectors. Does anyone have any potential diagnosis and fix?