According the Honda CBR F2 91-94 Service Manual, page 6-14, to adjust the idle screw you need to:

[ul][*]make sure the carburetor synchronization is within specification before pilot screw adjustment (see page 1-6)[*]Use a tachometer with graduations of 50 rpm change.[/ul]My questions:
[ol][*]My bike has just over 21,000 miles on it. If I'm going to do the carb sync, shouldn't I first adjust the valve gaps?[*]Where can I get a tach with that sort of accuracy? Where would I hook it up? What kind of cost? Is it really necessary?[/ol]Here is what is says to do this adjustment (there's also a disclaimer at the top and a High Altitude instructions)
[hr][blockquote]Pilot screw wrench 49-state and california type:
07KMA-MN90100 or
07MMA-MV9010A
Canada Type: 0790-473001
[/blockquote][ol][*]Turn the pilot screw clockwise until it seats lightly, then back it out to the specification given. This is an initial setting prior to the final pilot screw adjustment.

CAUTION
Damage to the pilot screw seat will occur if the pilot screw is tightened against the seat

Initial Opening: 49-states type: 2-1/8 turns out
: California type: 2-3/4 turns out
: Canada Type: 2 turns out[*]Warm up the engine to operating temperature.
Stop and go riding for 10 minutes is sufficient.[*]Attach a tachometer according to its manufacturer's instructions.[*]Adjust the idle speed to the specified rpm with the throttle stop screw.

Idle Speed: 49-states and Canada type:
1,200 ±100rpm
: California Type: 1,400 ±100 rpm[*]Turn all pilot screws 1/2 turns counterclockwise from the initial setting.[*]If the engine speed increases by 50 rpm or more, turn all pilot screws out by successive 1/2 turn increments until engine speed does not increase.[*]Adjust the idle speed with the trottle stop screw.[*]Turn the No. 3 carburetor pilot screw in until the engine speed drops 50 rpm[*]Then turn the No. 3 carburetor pilot screw coutnerclockwise 1/2 turn from the position obtained in step 8.[*]Adjust the idle speed with the throttle stop screw.[*]Perform Steps 8 , 9 and 10 for the No. 1, 2 and 4 carburetor pilot screws.
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