pneumatics tend to be a bit "bouncy" as they have more deflection than most FRC wheels.
When contacting or impacting obstacles, this is generally a good thing. When trying to get precise positioning of a large arm, this bounce can look like bobbling.
In 2010, 33 went over the bumps by lifting the middle wheel which caused a smoother transition. This worked very well until States that year when we noticed the rear axle was bent. Basically as the driver got more confident and faster, he was literally driving off of the bump. This meant that the back wheels tended to see repeated 8-10" drops multiple times a match... So the axle had to be "beefed up".
Also in 2010, there was a very good team that was an 8x8 with hard wheels that nearly knocked themselves out of elims by what we assumed was a CRIO reset after crashing over the bumps hard.
I saw a lot of broken wheels and axles in 2010 and 2012 due to impacts.
As others have pointed out, using angled skids can help go over bumps too.
This was one of my favorite pictures from 2012:
https://www.flickr.com/photos/daniel...7629155165512/