Nuru,
I've noticed the bounce with my 4100 HST which I've had for just two months. I figured it was the nature of a smaller compact tractor. I came from a 1944 Ford 2N with loaded tires and wheel weights. It didn't bounce! I'll check the tire pressure tomorrow, and may consider loading the rear R-4 tires with RV anti-freeze. The traction is great in FWD but leaves a lot to be desired when disengaged even with an empty FEL.
Like TerryinMD, my spare cinch pins are mounted in small welded loops on the left (not adjustable) 3PH link. I did get a rubber cord with my tractor but it doesn't have the handy pockets.
I'm not attaching any photos of my 4100 because it is a mess. The day before the ground froze I was digging a diversion ditch in very wet, soft ground. I buried it once (that day) and had to "walk" it out with the FEL. It was just below freezing and I couldn't wash it up. Maybe during the January thaw! Happy New Year!
Duane