My wheelset is almost finished!
The GP 5000 STR wheels were mounted without tire levers, and the complete set looks fantastic!
I also ordered the valves and tubeless tape from CarbonSpeed, but no project is without problems...

Front wheel mounted, and the wheel maintains its air pressure without tubeless lubricant.
Rear wheel loses air after about two hours.

I'm a complete "newbie" should the wheel be leak-proof without tubeless lubricant, or will it stay permanently with it?
The tape is probably not mounted properly?!
2nd question: I removed the valve core to fill it with tubeless lubricant later – reinstalled it for testing – and now the valve is completely leaking.
What am I doing wrong?