A steam cleaner might work well to flush out the grit and gunk from those areas.
Just make sure you service the bearings if the hubs have non-sealed bearings in it, as the hot steam might also flush out all the grease in the bearing races.
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72 Line Seeker
83 Davidson Signature
84 Peugeot PSV
84 Peugeot PY10FC
84 Gitane Tour de France.
85 Vitus Plus Carbone 7
86 ALAN Record Carbonio
86 Medici Aerodynamic (Project)
88 Pinarello Montello
89 Bottecchia Professional Chorus SL
95 Trek 5500 OCLV (Project)