>>1313288>assume i have a time machine, what would you suggest for training?Get a copy of The Cyclists Training Bible, and do the 3 months of Base Training. That's not too hard really and when you get done with it you'll be a fitter rider than 9 out of 10 average casual recreational riders.
But you don't have 3 months, you have 2 months, and your apparent current level of aerobic endurance is only 20 miles at a time.
Really what you need to do is go back a YEAR in time and start training *then*.
People train for *years* for Ultraendurance events, and 300 miles in 2 days is more-or-less an 'Ultraendurance' event.
It doesn't even matter if you have all day those 2 days to ride 150 miles, that's a lot of miles on back-to-back days.
I don't think you're going to make it. You can do whatever you want to 'train' for 2 months, but if all you can do now is 20 miles and that's a 'big ride' for you, then I stick by what I said before: you'll maybe, *maybe* get through Day #1, but if you do you'll fall apart on Day #2, assuming you can even *move* on the 2nd morning.
I've been riding hard for 10+ years and I wouldn't want to just jump into a 2-day 300-mile ride without spending a couple months training *on top of* all those years of training.
Do whatever you think you can, but if you can't ride 100 miles a day two days in a row by the week before this 'event' of yours, then you're not going to make it. Since you likely won't be talked out of it I sure hope for your sake this is some planned, fully-supported 'event' and not just you on your own or you and a couple buddies going out on a 300 mile lark. At least take a cellphone with you so you can call for a ride home when you bail out.