The European trips on long range 777s are all first suite equipped now. About half of the 747-400s have been completed. UA is not yet announcing in advance which 744 flights are first suites until about a day before the flight.

So you can't presume the 744 will or will not have a suite. For example, though, out of the past 7 days from LAX-NRT, there were suites 6 of the days.

BTW, there are two flights a day from NRT-SFO. The later of the two is a 777 that will have suites, if you want to make sure you have them on the return flight.