5mm bore, mod1 pitch pinion

I just ordered one from starluck - all they had was 14T and smaller. I also have a 20T from Mike. I like the ones Mike makes, they are a little trimmer and fit better in the casing.

I am pretty new at this, but the 9XL is a great motor for the price. I had to wait several weeks for the parts too, but well worth the wait.

I have a similar set up as you:

8XL with heat sink (definitely get the heat sink!)
12020
strobe slipper
UBEC

The 20T gets the controller just a touch on the warm side, so I am waiting for the 18T. If I could re-do it, I would have bought both.

I would suggest waiting, BUT order what is in stock now.