The manual that came with my Koyker 160 loader said that the break away was in the 1200 lb. range. The tractor it was mounted on was a YM 3000 2 wheel drive, the axle and front tires would never support that extra 1200 lbs in the 5 foot bucket. If you have the joystick control, there is a relief valve that can be adjusted with a socket wrench under a cover on the joystick. After some thought, I set the relief valve so the bucket would still lift the tractor front end, but that's about all. With that setting I was still more than able to load a full struck bucket of crush rock or dirt and still have more lift capacity if needed. I don't think the front ends of the 2 wheel drive tractors are built to stand the extra load that would be applied using the full capacity of some of these aftermarket FEL units, not to mention keeping the rear wheels on the ground. Maybe thinking about it differently might prove to be useful, sure would be safer. Thinking about how much lift do you need from the FEL, setting the relief valve to that point + a little might prevent damage to the front ends of these little tractors. At least that was my thinking as I was setting mine.
Chris