To change to a heavier gauge of strings you need to tighten the springs, reset the intonation, and possibly adjust the truss rod tension. If your not accustomed to working on guitars you may want to take your guitar to a qualified guitar repairman who is familiar with Floyd Rose systems. But if you want to try it, here’s what you do...
To change to a heavier gauge of strings:
Replace all your strings with the heavier gauge strings and tune the guitar to an electronic tuner
(leave the nut clamps un-clamped).
Check to see if the base plate is parallel with the body.
If the base plate seems to be tilting up away from the body, increase the spring tension and re-tune.
If the base plate seems to be tilting down closer to the body, decrease the spring tension and re-tune.
Repeat steps 2 and 3 until the base plate is sitting parallel to the body.
To intonate a Floyd Rose Bridge:
Check the intonation:
Tune all the strings on your guitar to an electronic tuner with all the nut clamps released.
Determine if the intonation of the string you wish to change is sharp or flat by chiming the string directly over the 12th and checking the tuning. Then, carefully press the string down to the 12th fret and check the tuning again with the string fretted. If the fretted note is flat when compared to the chimed note, then the saddle must be moved toward the nut until the chimed note and the fretted note match. If the fretted note is sharp when compared to the chimed note the saddle must be moved away from the nut until the chimed and fretted notes match.
To move the saddle:
Once you have determined which direction (toward or away from the nut) to move the saddle, loosen the
string until it is limp.
Loosen the attachment screw holding the saddle to the bridge plate while holding the saddle in place. Move the saddle in the desired direction a small amount (about 1/16in on the first adjustment and your best guess on subsequent adjustments) and re-tighten the screw.
[Note: If the saddle will not move forward because it is resting against the attachment screw, you can move the screw to the next hole forward on the bridge plate. This will give you more adjustment range. Also, if you need to move the saddle away from the nut to a position where the attachment screw can no longer clamp the saddle firmly, you can move the screw to the next hole back on the bridge plate.]
Re-tune the string and check the intonation again using the procedure outlined above (check the intonation).
Repeat this cycle until each string is properly intonated.
When you’re finished with the intonation procedure re-tighten the nut clamps and re-tune the guitar with the fine tuner screws. This will not change your intonation setting.
Since you are changing to a heavier gauge set of strings you should check the curve of the neck. A perfectly set up guitar will have a slight forward bow in the neck. If your neck has more than a slight forward bow you should tighten the truss rod until the bow is slightly forward. If your neck is perfectly straight or back bowed, you should loosen the truss rod until you get a slight forward bow.
If you make a neck adjustment you may have to re-tune the guitar.