There is absolutely nothing you can do on the bike to make you ride that 50-miler faster, if you haven't done the training already. But there are lots of things you can do on the bike to make you slower (like doing way too much between now & then). Take Thursday off altogether & rest - feet up; not gardening. Then on Friday ride 20 miles at medium (talking) pace and throw in a few (3-5?) one to two minute harder efforts with about the same rest in between - just to loosen the legs and get the heart going.
Between now and Saturday, drink lots (water not booze!) and eat some carbs. Drink & eat often and light on the ride - one bottle of water per hour. Start to drink at the 15-20 minute mark (not the whole bottle at 59 minutes!) and drink every 15 minutes.
And on Saturday, don't ride into the red zone unless you do this often on your normal rides. Pace yourself - try to start at the same pace you aim to finish at. Don't go
[email protected] out for 20 miles with a load of fast guys and grovel the last 30 in purgatory.
