Fire Hazard, I believe he means how to get it in the pacific standard heist (final heist).
That is what I was referring to as well - after you do the bank, you have to exit and run to the bikes all during which your reward-money is slowly decreasing (it reportedly stops decreasing once everyone is on the dinghy/boat), no?
Once you get to that point, unless they patched it, you could try one of the options I mentioned.
EDIT - another thing you could try, if you haven't already, with any vehicle choice (bikes included), is the highway -
When you leave the alley the bikes are in, you could try going to the highway (your first turns, if I recall correctly, starting from the alley with the bikes, would be:
right turn (going out of the alley)
left turn (at the intersection close to the alley)
follow the yellow-GPS line and turn left where indicated (on the straight road before the left turn there should be a jump on the right side of the road you could use if you are using the bikes as I believe there is a roadblock next to it)
after-which to your right should be the highway