There's a pretty simple way to cheese this one, providing you're not above cheesing achievements.
Basically, load up any level that has a pool or fountain etc that you can grind endlessly on (I used the fountain in the centre of the Downtown Minneapolis level).
Once it loads and starts, pause the game and go down to game options, mods and then turn on "perfect rail balance" and "perfect manual balance". Now just do a bunch of flips to manual etc (to get the combo meter going) until you get to the pool/fountain, and then just flip into a grind and wait until you have more than enough to equal 100,000 points. Now pause the game again and turn off the mods, resume the game and just let the character lose balance and bail.
Here's a quick video that shows it in action: