At high speeds, how much of a difference in speed can it make being tucked in properly, as compared to a less experienced rider trying to tuck in as best he can. Everyone has different form and I'm the less experienced rider. Can a proper position make as much as 5-10 mph at high speeds? My size is 170 lbs and about 5'10'. I'm not a big guy so I know the wind drag isn't killing me, but I'm sure I could do better. I'm riding a 6R by the way.