For Kick serve - relation to American Twist unknown.
Stroke spin and pace are closely related only to about 4 milliseconds of racket-ball contact. There are few competent sources describing those 4 milliseconds.
Suggest that you purchase the reference book,
Technical Tennis, Cross & Lindsay for a clear explanation of how rackets contact the ball for various spins. Great illustrations and a logical analysis. Readable.
I took their descriptions and looked for the kick serve, looked for racket to first contact the upper half of the ball. I found a few examples and that is what I believe. Researchers said it and I saw it myself in high speed videos. My conclusions are based on very few observations. More observations are needed to confirm. Racket face closed at around 15 d is my current best estimate based on a few video observations of likely kick serves. Toly posted some early posts, 2013(?), on the closed angle of the kick serve. Great illustrations. I probably read them but did not pick up what he was talking about even with the clear illustrations.....
For stop action single frame on Vimeo: click "Vimeo", full screen, hold down the SHIFT KEY and use the ARROW KEYS.
A racket must be
closed to first contact the top half of the ball. (Note - this fact is very useful because you cannot see the racket strings contacting the ball but you can usually see how closed the racket is just before impact - all with low cost high speed video cameras!) To check this out get a racket and ball and look - Close the racket face and look at where contact on the ball is. Open the racket and look at where contact is. Have the racket neutral between open and closed and see where contact is. Then use the reference book to see what Cross and Lindsay have to say about ball & racket contact.
(My definition of a
closed racket - the highest part of the racket face is more forward in the direction of travel than the rest of the head.)
If you practice without this closed checkpoint just before impact, Cross & Lindsay's description and my few video observations indicate that you probably never will get the bounce to the right of a kick serve. Have any other references on this subject?
The above is the tricky fact that is very hard to find discussed. There is another racket motion for a kick serve. The racket has to rise before during and after impact. I did not know how that came about and looked for high speed videos of it for years. Here is Toly's gif showing what happens, before impact, at an instant during impact, and after impact.
link
The Waiter's Tray technique - the most common technique used by more than half of active tennis players - does not appear to have a way to apply heavy top spin and pace to a serve, a way to make the racket rise during impact. WT can hit slice though.
There are many threads on this kick serve issue. Here's one related post that shows how the racket rises.
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"Your toss depends on your serving technique. Your serving technique is unknown. There is a lot of variety in poster's 'kick' serves.
First, the Waiter's Tray technique is used by probably over 50% of active tennis players. All servers interested in serving technique should first check their serving techniques.
A tell tale checkpoint for the high level kick serve is the angle of the forearm-to-racket at impact. The angle has to be smaller so that the racket can still be rising as it contacts the ball. The flat and slice serve are seen to impact the ball closer to the highest point that the racket reaches. If you don't know what to look for you will not see it even with high speed videos.
Forearm-to-racket angle for impact of the kick serve. The racket can rise more effectively during impact. For this relatively lower impact location either the ball has to drop lower or the server must jump higher.
Forearm-to-racket angle of slice serve for comparison.
If you do not use the high level kick serve technique, I don't think there is any vetted advice for how an unknown kick serve technique should be performed.
While the ball is impacted more 'over the head' for a high level kick serve the head moves forward from toss release to make that happen. So the often heard advice 'Toss the ball over your head for a kick serve' is not what is seen in videos of most high level kick serves - the head moves forward. Look at the head location at toss release and head location at impact.
For comparison to slice serve
https://tt.tennis-warehouse.com/ind...-do-i-hit-a-slice-serve.574777/#post-10708267 "