read this, it may help.....
XI. Unique Jump 11
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Location: Callahan Point, Portland
Advised Car: PCJ600
As you are travelling down the one way highway, look to your left and you
should see a stone wall. Drive through and look to your left and you should see
a rampway and a donut behind it. You'll have to go through the donut and land
in the car park to complete the jump. Back the bike up and speed forward.
Gently push the analog stick forward to lean forward on the bike and connect
with the ramp, pass through the donut and land in the car park to complete
the jump.