How long is your ride for? Personally, I would never have gu's. They spike your insulin and create an uneven energy curve in your body that leads to crashing or feeling rubbish post ride.

When I personally ride for close to 90 miles / 140 kms I'll have a big carb meal the night prior and don't eat breakfast. Although I do have a handful of raw nuts so the black coffee doesn't make me peak! Then I will have bananas and/or good quality bar's once every hour during the ride. That will sustain you plenty. A protein shake is best following a ride. The body takes longer to break protein down, so having that pre-ride may actually be having an adverse effect.