Bearing problem

Hi, i am from team 1396 and 2 of our bearings keep popping out no matter what we do, is anyone else having this problem?
we get them on the chain and run them for about 15 seconds before they pop out, any help would be very helpful.
Thanks in advace,
Team 1396

Are you talking about the bearings in the wheels?

If so, do you have spacers holding the wheel centered on the axle? if not, you might try making some spacers to fit between the bearings and the chassis, and putting them on the axle on either side of the wheel, so the bearings cannot move sideways.

we are in the middle of trying that, heh we need washers to fit inside the inner sprocket

i really dont like the reason they didn’t give us 4 sprockets ;_;