Zero is correct for a stock bike. I added 2 ponds to mine, but this must be done with no weight on the bike! You have to place it on a center rest to elevate either end that you want to add air to. Otherwise you run the risk of putting in too much pressure. I added only 2 pounds to both the front and rear and obtained better ground clearence (for those of you who like to scrape the floor boards) but what it really added was better stability at speed.