Originally Posted by Topspin Shot
Thanks, WV. I looked at Groth's motion and Tanner's, and they don't get the arm vertical either. Maybe I don't need it?
You don't need it. The power is going to come from having quicker more relaxed movement and a good kinetic chain. For example, Groth is a big guy who gets a huge amount of hip rotation into his serve, so he's using his strength and body weight to his advantage.
I'm less knowledgeable about Tanner's serve, though I've seen some old videos. I believe your motion is slower than his. He almost hit the ball on the way up.
Some advice for video of your serve. If you can, place the camera on a tripod behind you, or have someone hold it so that you can see your movement from closer. Also, shoot the serve from the side so that you can see how you move into the court.
I have a quick motion, too. So perhaps that's why I like your basic serve motion.
Keep smashing them and keep your shoulder healthy.