A Grand Prix isn't such a rare and special bike that you can't do whatever you like with it. I like the sound of what you're planning, except the 52 ring up front sounds pretty crazy to me too, unless there are no significant hills on your routes. The IGH sounds like just the ticket for your rainy and dusty Cambodian roads, but don't forget the fenders, too.
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● 1971 Grandis SL ● 1972 Lambert Grand Prix frankenbike ● 1972 Raleigh Super Course fixie ● 1973 Nishiki Semi-Pro ● 1979 Motobecane Grand Jubile ●1980 Apollo "Legnano" ● 1984 Peugeot Vagabond ● 1985 Shogun Prairie Breaker ● 1986 Merckx Super Corsa ● 1987 Schwinn Tempo ● 1988 Schwinn Voyageur ● 1989 Bottechia Team ADR replica ● 1990 Cannondale ST600 ● 1993 Technium RT600 ● 1996 Kona Lava Dome ●
Last edited by Lascauxcaveman; 10-30-13 at 07:55 PM.