When you lift the front wheel on a bike (e.g. with a manual) are you pivoting about the rear axle or the rear tyre contact point?
The reason I ask is that I've been messing around, sticking my bike in a turbo trainer that clamps to the rear QR. With this setup I find it very easy to lift the front wheel as high as I like just with a weight shift, but my attempts to do the same while riding along are still pretty rubbish. They usually consist of a dozen attempts where the wheel barely comes off the ground for more than a second, followed by one where I end up dumped on my arse on the trail feeling sorry for myself. Then it's back to tentative again.
So, I'm trying to work out whether there is any physics reason (i.e. a different pivot point) that makes it easier to lift the front wheel on the turbo (which definitely pivots about the rear axle) than it does on the ground.