My 2000 800 RMK is having low end issues... It sputters and bogs until about 4,000 RPM, and a few times, wouldn't come out of the bog, even under full throttle... When it does come out, it takes off like a rocket... Kinda unsafe... I have pulled and cleaned the carbs, and that didn't help... Any ideas? Could my secondary be causing any of this? Any new ideas would be great! Thanks!