What do u think about the sound of the engine?
Seems to sound good in the first video, idle is a little high. Turn it down to 1200-1400 once fully warmed up.
Second video, I hear a little valve noise, nothing crazy, a carb sync should reduce the noise and make it run smoother. Good idea using the temp gauge to determine all cylinders are firing.
Are you running the bike in your house?! [my wife would flip out!]
And BTW - dont let it idle for long periods of time [over 5 min], this is an air cooled bike. If you have a fan, have it blow on the front of the engine when idling in place.
I know it's winter but are you able to test ride it? [77 degrees down here today!]
Looks like a nice bike, you'll get there!