Sorry batman, the 18" tire is just under 3/4" ( .7" ) larger in diameter than the stock tire. But this only raises the rear axle by half of that. So the rear axle is less than 3/8" higher than with the stock tire. But wait, there is more...
The stock footpegs are closer to the front axle which is the fulcrum of the ark of the rear axle. The pegs are about twice as far from the rear axle than the front, so they get raised about a 3rd of what the rear axle got raised. That means my 18" tire raised the pegs by less than 1/8".
So you are saying the only reason I could ride that bike to and from work every day for months was that the 18" tire that raised my footpegs ~1/8"?????
I must be one lucky bastard!!