on a motocross bike you should be standing most of the time, and also you are much more forward on the bike so it does not have the disconect that you would feel on the road,
Chris Birch is no where near 6 foot 3,
personally i dont run rises, just a taller bend of bar, handlebar and lever set up is a personal thing, and the latest trend in MX is low and flat, and pulled back further and leavers higher than what it was 10 years ago,
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