A track combine turning within or nearly the same radius as its wheeled counterpart can be a blessing and a curse. Blessing, because it is convenient. A curse, because unless the undercarriage and supporting chassis is not beefed up considerably over its wheeled version, then disaster might be looming. I looked over the wheeled and tracked versions at the Farm Progress Show and did not see any noticeable difference between the 9120 and an 8120, which appears to be nearly the same as the 8010. If a track and a wheel combine can turn within the same radius, the track is exerting around 30-50% more force on the chassis (same with a tractor), depending on conditions. That's why track chassis are always heavier. It doesn't seem to be the case with the 9120 though.
Actually Muddy the torsional forces on the combine would be far higher, at least on the quadtrak articulated tractor the forces are shared by the front and back tracks as they are turned in opposite directions
Additionally at times the weight on the tracks once you add large header, full grain tank, are far higher than the quadtrak would ever carry.
These look like they're straight off the quadtrak, an in house quickie track set-up. That they are not factory installed tells that tale.
We simply have to trust engineering on things and hope for the best.
My original point has to do with the apparent tighter turning circle of the CIH vs Lexion.
Don