Looks great but a bit difficult as first trial :)
My issue was when I stuck at the slope I had almost no solution, just restart. Tried to push back and start again (eg Level 1) but did not help. But maybe that is the challenge ;) Some visual feedback would be also fine about rpm or some 'torque meter' to indicate if I should shift up or down.
But anyway, nice game, I will spend some time to try to solve the levels :)