I wouldn't necessarily recommend trying easier spots. That's good in the beginning, but the way you really get better is by sitting down with a spot for hours and really figuring out what you need to make it happen.
With this, I think you're trying to bump it too much like it's San Andreas. In this game, you get better bumps from the engine than you do from the back wheel. Move the packer closer, tap lean forwards all the way up the packer, and lean back just before colliding with the sign. Good luck
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