what causes my thunsercat to jerk in all gears on a steady throttle?
throttle position sensor
The dude that got a swirly at that gears event? He's a jerk, but that video was hilarious.
More than likely, bad motor mounts
Jack's mannequin, Jakalope, Jars of Clay. Jump Steady, Junction 18, Jerk. (Jerk is a band, I'm not calling you one. ;) )
When a throttle cable is too tight any slight tap on the gas pedal could cause the car to jerk forward. The throttle cable should be adjusted to allow more play on the pedal.
Lack of transmission fluid.
they make it so the bike doesnt jerk around and stall when shifting gears and so you can shoot out of turns
If its an automatic its your tcc selenoid in your transmission take it to a dealer! very labour intensive
Throttle position sensor
The "lockup torque converter" could be engaging too soon. Take it to a transmission shop to have it diagnosed.
It is most likely your HT leads or coil pack.
your transmission wears after time, try getting a fluid change, use fluid made for older cars this should help slow down wear and make the jerk much less noticeable