This is what I am talking about. The pin on the slide height adjustment screw (idle) isn't long enough on my son's TBR7. It makes a barely perceptable change when it is warm, and no change when it is cold. I need a longer pin at the end of the adjuster screw... OR as Jerry suggested, I can remove the screw, and file the post that the screw mounts into so that the head seats lower. It is a good idea, and I know it will work. Of course, I will want to make sure the aluminum shavings DON'T go into the carb. No problem. I am sure even a 1-2mm shave will be effective. The pin would lift the slide by a mm or two for cold running.
But the weather is HOT here in Kansas City. The thing starts up instantly and idles fine. This is a COLD weather issue!!!
https://www.chinariders.net/showthread.php?t=30763