I just put in a new (to me) motor in my 95 CBR and there are some things that I was wondering about. It has a +4 ignition advance in it. It seems to be idling rough kind of choppy but the RPMs are steady, the throttle is also choppy and not smooth. Could this be because of the ignition advance or is it something else. Also when I give it gas and let off the RPMs seem to drag a bit, like they fall from where I let off down to normal idle slowish. Thanks Ill post a video tomorrow.

 

i kinda have the same issues...drags going back to idle...my idle fluctuates though...+/- 100rpm...

 

Check you air intakes... sounds to me that you might have an issue in that area. Make sure everything is connect correctly and also make sure there are no air leaks (loose connections or bad hoses). I connected up my hoses incorrectly one time and made my bike run like a lawn mower. It also did the same thing when the carb insulators bands came loose on my way to work.

 

Spark plug wires were not on the right cylinder. Fixed it.