I have a 1993 cbr900 i bought a brand new battery and 2 days l8tr it was dead what will cause my batteries to keep getting drained while riding my bike??

The bike is not charging the battery up,,,or your using more amps than the bike can put out,,,have you fitted more lights to this bike?? do you do a lot of stop starts,,only running the bike for a short time? check the charging system first with all the lights and flashers on it should just charge an amp or so into the battery if its not change the voltage regulator first get a heavy duty one not a cheepy?

The first place I would look is the voltage regulator. When they start to go out, they will continue to drain amps from the battery even when the bike is off. An ohm meter can test to see if there is continuity there when the bike is off. If so, replace the regulator. Pretty easy to test/diagnose the regulator.