Owenski

Ahhhhh Mr Thread, I've been expecting you...

Not had my bike topple personally but I know you're not the first. Its worth not putting the cover on when its so windy thats for sure.

I left mine outside Uni last friday and at every oportunity I snuck a peek out at it to make sure it was still standing. Unfortunatly there is very little choice about which way the bike can face while parked there and the wind was hitting it side on, in the strong gusts it was noticeable that the bike moved. I'd imagine a cover will give that extra surface area for the wind to hit, and the increased air resistance will be just enough to topple most bikes.