My ride is a 94 R100 GS. A couple years ago, I rebuilt my carbs. I did them one at a time starting with the left side which went very smoothly. So smoothly that I was very confident with the right side. All was going well with the right carb but during reassembly, my mind wandered and while screwing in the idle mixture screw, I tightened it very hard. I realized at once what I had done but too late. I replaced that mixture screw with a new one but I'm concerned I messed up the seat. I am wondering what the consequence of this may be. I understand that the idle mixture screw actually does not change the air to fuel mixture but sets the amount of mixture to proceed to the combustion chamber. If this is true, then an enlarged mixture screw seat will only affect the performance at idle and maybe a little more RPMs.
Is my understanding true or am I way off base? Thanks in advance.
The screw on the bottom is the idle MIXTURE screw. It adjusts the idle mixture. The amount of fuel getting to the cylinder is dependent on other things such as butterfly (indirectly). Gently bottom out the screw and back out 1 1/4 turns. With engine warm after a several mile ride, adjust the screw for the highest idle speed. If this adjustment does not change the speed there are likely other problems including possible damage to seat.
If the idle speed peaks near the 1 1/4 turn starting point you should be good to go.
This all assumes everything else has been set such as valves, cable slack, enricher cable slack and timing.
Bob
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