Dears,

we're planning a 220km ride in early September. Last year we did the 150 version of the same ride. Stopping at every support station and eating what was there (sports drinks, sweet baked goods, bananas, a sandwich at lunch) worked fine but cost us too much time (9 hours total). The cutoff is 12 hours for the 220.

I'm planning to install a saddle mounted bottle holder to have one bottle of a highly concentrated mixture (either diluted gels or self-made maltodextrin mix) plus 2 bottles of water.
I will also have a top tube bag full of stuff & some more bars or a bag of salted nuts or so in the jersey pockets.

If worse comes to worst (weather wise) we will have a backpack (for rain gear) (we're not going if it pours) and more solid food.

I'm mainly wondering about the liquid stash - how many calories can I pack into that bottle full of goop.

Any further suggestions? Note I can't buy all US brands over here but we get Powerbar, and Hammer gel (which looks good 'cause you can buy big bottles)