Out on a limb

Generated image of a boy going out on a limb
To go out on a limb means to take a risk by saying or doing something that others might not agree with.

The phrase comes from the image of climbing far out on a tree branch. The farther you go from the trunk, the less support you have, and the greater the chance the branch could break.

I might be out on a limb here, but I think their small startup could become very successful.