Well, all of the above... :)
The poster who started this subthread to which I was responding noted that altho had sizable cylinder on a tractor loader that didn't have anything close to the lift force that one might expect simply from the bore/pressure of the cylinder and the responder directly ahead mentioned only the weight of the loader itself as a confounding factor...
A typical small/medium tractor loader is generally a very simple mechanism a la the one shown at the link below--
While there are complex mechanisms found on either very large and/or expensive loaders and/or the compact loaders such as the Bobcat and ilk, a basic loader of the above type doesn't have mechanical advantage--the upward component at the bottom is fairly small and the relatively long moment arm beyond the lift point (necessary to get reasonable lift height, etc.) requires quite a bit to counteract.
I was simply trying to be concise at, perhaps, the cost of some clarity in pointing out that mechanics are a part as well as weight and cylinder force...as per usual on usenet, the opportunity to seek advantage and display perceived intellectual prowess at expense of others is, apparently, irresistible force for some. :(
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