Boundary conditions

Hello all,

I have a small question. In the appendix, there's a picture of the frame of an electric scooter (only the bottom part). I have used roller BC's as shown but when I take a look at the max. tensions, they are not quite situated in the middle (which a beam will do). I have tried certain alternatives but none help. Any ideas on how to simulate it properly?

Thanks in advance,

Kind regards.