Quite interesting comments. Id like to believe that someone with SGB's experience and various bikes that he rode could give a well formulated opinion.
I've only had one bike all my life.(Did change the front to a 21er however which costed less than R4k) Im no ridinggod, and not defending my choice here.
A Dutchman once stayed over at my place. He used to design Choppers. He told me about 7 variables that influence the behaviour of a bike's front end, behavoir, steering etc (geometry). Rake angle, fork length, wheel diameter, front end height etc.
By changing a 1200's wheel diameter you change the geometry. I experienced that without a doubt on tar. All of the suddend the bike started a headshake around 170km/h which it never did. About gravel and sand riding we dont have to argur, I know what I know. All Im saying is that the difference is not marginal.
Im in the process of selling my bike, but will remove the front wheel if I might buy another 1200 in the future.
One question however: How many bikes in the Dakar with a 19er at the front?