Change in the construction [Updated]

grabcad

To minimize suspension impact with minimal wheel assembly changes, alter distance "b" or both a and b. As distance 'a' is fixed, increase 'b'; original assembly had b=65.51mm, altered to 425.91mm (6.5x decrease). To achieve a 7x force reduction (8400/1200), adjust 'b' to ~460mm (35mm more than current alteration). Remove unnecessary parts and simplify others like wheel arm and old brackets, but this version didn't include that. Units used are mm and pounds, but inches and pounds in assignment don't matter as long as proportions are expressed correctly.