Topic: 2000 Nighthawk 750 Bogs at 6k RPM

[Andrewcho]

I have a 2000 CB750 that is not running right. It only gets 20 mpg. The problem is when the rpm gets to about 5-6k. It almost stalls out for a second then picks back up(feels like rev limiter). This happens under no load as well as under acceleration. It also can't go over 80 mph (80mph is about 6k rpm). The problem is less noticeable in weather below 50f. The problem started to happen after I used seafoam. I cleaned the carbs and it helped for one day but started happening again. If I slowly rev the engine, the problem still happens. Always around 5k. Any ideas?

[CBJoe]

When you say you cleaned the carbs, did you fully disassemble, inspect and clean all jets/components, and rebuild with kits?

Did you verify float heights?  The fact that it started after you used seafoam leads to believe that its still some crud or deposites fouling things up.

Joe

[Andrewcho]

It was a quick disassemble and spray with carb cleaner. Blew the jets with compressed air too.

(Sorry for the late reply)