Hi Will, cheers. It's a fair idea to use some sort of leverage mechanism, but the problem is that I'm past that point. The whole design has been based around this linear actuator, and redesigning would be difficult and costly at this point, especially since I have basically all my parts ready. The other thing is that using a lever to increase the speed of the lifter would put extra force on the linac. Not only will a new motor increase the speed of the linac, it will also give increased torque (and thus force), so there doesn't have to be a tradeoff between the two. I've been looking into brushless motors with a similar diameter (and shaft diameter) to the current one today, if I could get sufficient speed and power from one of those then I'd just be able to straight-up replace the old brushed motor, no custom gearbox required. It's just a little difficult finding a brushless motor of the right dimensions that will run on a 5s lipo.