Cam break-in Questions.... On an engine run stand

I use a electric pump so I don't have to crank and crank to fill the carb, also set the timing manually before ever starting it.
The oil system is primed and when it starts on the first crank it at 2000 - 2500 + rpm and I turn it down to 2000 for 20 min and have never had a problem
Can't you just pre fill the carb? I did.