Creo simulate difference between solid and beam calculation

Hi All,

I have a fairly simple question I hope, but for some reason can't figure it out myself.

When I run a simulate analyses on the shaft below I'm reading much higher stress results than what I calculate by hand. But when I run the same analyses on a beam section the results are lower than the hand calculation. For this reason I'm not feeling very confident on the results at the moment.

The situation is as followed:

The shaft has fixed displacement contraints on the pink surfaces with all rotational movements "free" and also axial movement free. On both outer ends I have placed a planar contraint to make it "fully contraint".

The load is a radial bearing load on the green section. The situation can be compared to the fin of a bow-shackle. 

Below the results of this analysis.

And this is the beam analysis:

And the results.

What am I missing here?

Thanks in advance for the help!