I put just a tad more than250lbs of beet juice in my 12.4x24's. With that and 140lbs/side of steel wheel weights, the back is still light if you have any load worth mentioning in the FEL. I use about 600+ lbs of concrete on the 3ph for loader work.
I built hub standoffs for the rear wheels, with a single 5/8 grade 5 bolt sticking out to hold weights. Years ago I got half a dozen round drops from the steel mill for a song - they were 1-1/4 x 17" diameter, weighed about 70 lbs each. Back then I used 3 per side on my L185DT. Now I'm using 2 per side on the L3200 - the other two are on my Cub Cadet zt mower.
Just buying the steel is, I believe, less expensive than buying real wheel weights, and then having them shipped to you. Fashioning your own mounts is pretty straight forward, whether you do a hub like I did, or come out with stand-offs from the Kubota wheel bolt holes.
Now that I'm pushing 70, I wouldn't care for any weights over what I have. 70lbs is a good number.
If you watch yard sales you might find 50lb barbell weights for next to nothing. They would not be hard to deal with.
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