2003 “Flywing” MX 100cc. Won’t start.

[EricE]

Hello all, new to this page.
Got this Flywing MX for $25. (Told buddy he had to charge me something because I didn’t want the “well I gave you a free bike!” Over my my head lol.
Anyway, I have replace almost all the electrical parts, I have spark. Sprayed starting fluid. Still won’t start !!! Kick start seems very mushy, Iam guessing low compression?
Any ideas would be greatly appreciated. Thanks!
And Any drop in engine ideas would also be a avenue I am willing to take.