Moyes, whose West Ham side are yet to win away from home in the league this campaign, faces the daunting challenge of trying to inflict City's first defeat of the season on Sunday at the Etihad Stadium.
And although he doesn’t dispute the quality within the City ranks, the former Manchester United boss believes they have weaknesses that his side can exploit.
"I wouldn't say they've got a long way to go but what I would say is they've not done anything yet as far as they've not won the Premiership [sic] yet," Moyes, who was parachuted into the top job last month after Slaven Bilic’s firing, told reporters.
"And I think there's been some great teams in the Premier League who have won it over the years. Maybe at the end people will say they are a great team but until that's done then you can't really say so.
"I think there are ways to play against them, I think they've got weaknesses. They play very high up the pitch, which can leave space in behind them.
"But I think the coach [Guardiola] admits to his frailties and knows what the weaknesses are but tries to make it so difficult for the opposition to get to their weaknesses."
West Ham and Man City experienced wildly different emotions in their midweek round of Premier League matches.