The simplest solution might be to get a different set of tyres with a much deeper aspect ratio. That 'might' be enough to give you a couple of centimetres? Otherwise I imagine it's going to be suspension work.
"Y mae dafad ddu ym mhob praidd"
1972 4/4, 1981 MGBGT, 1984 FLHT1340, 1980 XLH1000, 1990 ZX10
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