Wow, lot's of differing opinions. But in reality it's easier than all of this. Your body can only effectively process 24(ish) ounces of liquid an hour during exercise. So stay in that range and you will be fine, a little higher (maybe 28-30) for hot or humid climes.
If you're peeing with that much fluid intake, great. If not, that's fine too. Upping your fluid intake can't FORCE your body to process more than that. If you're going hard, you may not pee. Big deal.
Bottom line: Use the pee color thing to monitor hydration off the bike. Use hard numbers for fluid intake while on the bike. OP, your numbers of 120 oz for 4 hours are completely reasonable for the temp you list.
Steve