CBR 400 NC29 not pulling through rev range

Your revs are higher because the transmission is not shifting into the higher gear ranges. There is an apparent problem in your transmission that needs immediate attention. In the U.S., this is called "limp mode" and is designed to keep you from being stranded but to also make you so uncomfortable with the performance that you will take it for service as soon as possible. If it were my car, I would have it towed to a dealer for service. If you can't tow it, drive it SLOWLY to the nearest dealer while watching the tachometer and keeping it under under 2,500 RPM. Good luck.

sounds like fuel stavation possibly a blocked fuel filter or faulty fuel pump

Get some MAF cleaner & clean the Mass Air Flow sensor in the intake

sounds like throttle cable.replace both, and you can adjust idle with adjustment knob look under carbs for round knob about an inch big.

Blocked jets

1423 for old models below (Pre dbox)

1234 for newer models

Timing has been adjusted to high, or the spark advance is out of adjustment causing the revving

in this high a gear, and with the small cc of the bike, and age of it ,it just doesnt have enough torque in that gear unless you are going very fast. nothing is wrong, just save that gear for when you are going real fast

In the tachometer there is an integrated circuit that gives out of it 3 cables.The bike will not work without this IC plugged on the main clock's harness.