Here is another post in my 2022 and a half Temp X thread. This one is the installation of a big knurled knob idle adjuster.
I posted it elsewhere, and the threads and dimensions were accurate. It is post #5 in this thread:
https://www.chinariders.net/showthread.php?t=32024
OK, they cost under $3 so I bought a couple of them to keep as a spare. In fact, I bought an red one after that (maybe closer to matching my orange 5 speed)
Yup, the dimensions and threads were perfect. BUT, I reused the OEM spring which was lighter and wider. I also used a washer that came with the knob.
Oh, I had to start the bike and test it. TORTURE. It is 30 degrees out there. Sigh!