I tried negative acceleration and somehow, at the endpoint, the roulette sprite starts to rotate to the other direction. <img src="{SMILIES_PATH}/icon_e_sad.gif" alt=":(" title="Sad">
Try using clamp to stop it going too far:
[quote:250xzecn]clamp(x, lower, upper)
Return lower if x is less than lower, upper if x is greater than upper, else return x.
https://www.scirra.com/manual/126/system-expressions