Fork diameter of fzx700 is 38mm 1985-1992 vmax is 40mm and up from there is 43mm so you cant just swap forks.. unless the triple tree will fit max frame but then your talking about figuring out and modifying everything from headlight, handlebar bracket, crown, Speedo to fit on that triple tree. Then also you have a 135lbs curb weight difference between bikes roughly so I wouldnt reccomend it... alot of work for such little gain because the ability of what the smaller fork will handle will probably make the vmax handle even worse!
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