I found this on a forum:
"The Grand Prix of that era came with Weinmann 610 in front, and 750 in the rear -- allowing max. reach of 61 and 75 mm respectively."
(Reference: http://www.bikeforums.net/classic-vintage/389296-early-70-s-grand-prix-options.html)
@anidel started
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I found this on a forum:
"The Grand Prix of that era came with Weinmann 610 in front, and 750 in the rear -- allowing max. reach of 61 and 75 mm respectively."
(Reference: http://www.bikeforums.net/classic-vintage/389296-early-70-s-grand-prix-options.html)