The Cat 250X did not have top handlebars. The handlebars and forks were all one front end unit together and could not be seperated (aside from welding or cutting them off).
Judging by the color of your bike, it looks like you might have a 1970-1975 orange 250X (1969 the 250X was green, after that all 250X's were orange). Can you share pictures of your whole bike so we can make sure because the frame can tell a lot about whether it is a 250X or not.
If you do have a 250X then you more than likely have the incorrect front end on it. It's a Cat front end but is probably off of a 300X or 400X which had removable handlebars.
Here's a brochure picture of the 250X (the R2501)