03 GSXR 600 has lag in first gear how to fix it?

Question

FUEL INJECTED
ONLY HAS LAG WHEN YOU THOTTLE IT IN NEUTRAL AND 1ST GEAR .

Answer 1

Do you mean lag as in driveline snatch or lag as in the engine bogs down when you whack open the throttle? If chain drive, the former is sometimes accentuated by a excessively loose chain or one that's worn out. If the latter, yanking the throttle wide open at low engine rpms will suddenly drop the velocity of the air in the intake tract. A small stream of fast moving air is able to carry the fuel the engine needs. An equal volume of air except as a large slow moving stream allows the fuel to drop out and the engine starves for fuel. To examine this concept further, take a mouth full of water, pucker up your lips and squeeze and you'll squirt water halfway across the room. Take the same amount of water, open your mouth wide open and exhale and you'll slobber all over yourself like your great grandfather does at feeding time.