My 95 CBR 900 has problems thanks to mice. My bike ran perfect until mice got into the air filter box and made a nest out of packing peanuts.
They had it packed completly full. The bike would fall on its face and die when you hammered down on it because it could not get enough air.
I cleaned the filter box out and put a new filter in, but now the bike will idle just fine, but when you are riding along at a steady speed and about 3500-4000 rpm the bike misses and sputters. If you go ahead and crowd down on it, it picks up and runs good. Just don't like to run smooth at a steady rpm?? It only started this after I starved it for air due to the mice nest.
Any suggestions?? I have put in new spark plugs and checked the plug wires, they are ok.

 

Odd problem to have! I would check to see if they chewed away at any of the actual airbox housing. The 900RR's run horrible if they are modified in any way.

 

Luckly they did not chew on the housing and the housing is ok. The housing was loose on the carburetors so I am wondering if maybe when the packing peanuts clogged the filter and it couldn't draw air, it sucked air between the carbs and the housing and sucked in some dirt??
I am going to pull the carbs today and see if I can clean them. I hope this helps. I live in Indiana and I am running out of nice days to ride before it get too cold.

 

I got my bike fixed. Turned out it was a vacuum leak. Which brings me to another question. There is a vacuum line under #1 carburetor hooked to the intake piece. Where does the other end go?

 

should go to the airbox i believe what year is the bike

 

It is a 1995. I will look again, but I didn't see any place on the airbox it can go.