Does anyone have any tips for tracking the spike when doing j-stick? I have no trouble doing airplanes, but have trouble tracking the spike with tricks that require the ken to flip (like j-sticks and 1-turn airplanes)
Knees! The more you use your knees you'll be able to follow the spike around better. Sounds crazy but it works. And otherwise it is just a lot of practice. J-sticks are very much a "feel" as well as a visual tracking, at least to me.
I would focus on when you release the ken from the tama for the j-stick. In my experience, if you release (by release i mean 'flick out') the ken when it's at a straight point (meaning the bottom cup is facing perfectly straight up, not angled) the ken makes a more accurate turn in the air for tracking. I would also try following the ken in the air with the tama. I've found this helps rather than just releasing and waiting for the flip from a somewhat stationary position. I will also second what Ben said, knees help every trick. Hope this helped and made sense!
Yup, knees! Also in addition, try flicking the ken slower and more loft-y (using more knees would help!). It'll create more "air-time" for the ken making it easier to spot the spike then lace it! As soon as i can see the spike clearly pointing towards the sky, i focus so much on the point then it'll be similar to landing airplane from there. The more you get acquainted to slow/moderate ken flip speed, then gradually you start lacing them faster and get the feel for it! then try multi j-sticks!