ride times are very hard to say....there is always a chance of something on your bike breaking (which seems to happen a lot on this trail) and flats are always possible (one guy got 7 flats on this ride, but none were from thorns or anything) getting back by 12.....you can do that, but you will just be riding fireroads practically...all the bail out points are just down a fire road so its a waste to do that....the best way to go is on all the really nice desert single track they have there and it takes all day....ride time when i went was 4 hours 11 minutes about, the whole trip took about 7 hours...we had a broken derailler hanger and i had a flat...the derailler hanger took like 45 minutes to fix because the screw thing got jammed and my flat took a few minutes...so about an hour for the mechanicals and 2 hours worth of breaks/waiting for the group...not too bad, but this ride takes all day.....try to move whatever you have to do on saturday to sunday because this is a really awesome ride that isn't done too often...summer is too hot and certain trails arent supposed to be ridden in certain months for the big horn sheep breeding season, or something like that