Bump climbing issues

[archer003]

Hello all. Archer003 from 1982 here.
We have been working on the drive train recently, and we discovered a flaw in our design. When we attempted to climb over the bump, the bot couldn't make it over. We are currently working on attaching some new sprokets to try to gain more torque, but if it doesn't work we need to have our bases covered.

What I need, is some help trying to come up with ways to make our torque better, without using more CIM motors, since we are close to the max 5 as it is.

I included pictures of the front of our bot, the front wheels, and a profile of the current gear box. This is kind of a big portion of our robot, because it is too tall to go through the tunnel, so a quick response would be great. Thanks in advance.

~Archer003