I have a 900rr and it has power but I think it should have more. It has a tapping noise at all times. I changed 2 of the plugs and it made it a little quitier. Can anyone tell me what else it could be if it's not the other two. And the hose that is between the carbs is not hooked up to anything. I just bought this bike and want to make it a good bike. It has 31000 miles and runs great besides that. Can u help

 

If I'm ever in a position where I wonder what a sound is, I get my mechanic's stethoscope and see if I can determine the location. That would give me a more precise answer than asking someone to guess it over the net. If I can't pinpoint it, then I try to gather more info. Tapping can be valves which may be normal or it can be something worse.

The tube that comes out from the middle of the carbs would be then plugged into the housing for the sub air cleaner.
If you google [sub air cleaner honda cbr900rr] you will see the part that I am talking about. One can assume that it does some filtering before ambient air goes to what it is routed to: the carbs.

 

I have to make a correction:
Valves ticking, may not be so normal. I know that I have heard valves and others have mentioned it as well, but I can't really say as to how normal it is to hear how from the valve train. Yesterday I rode with my half helmet and didn't notice anything at all...used to be I heard a small amount of valve noise when I'd wear my half helmet.
Perhaps dead silent is the ideal....

 

When was the last oil change? Might be a good place to start as well.....