Edit- The first picture of Noracer's post didn't copy, but I'm referring to post #30.


If you look at the angle of lean for both the bike and the moto, they are pretty similar, so its not really the lean angle, its the body position on the bike that prevents a cyclist from getting a knee down.

As others have said, a moto is much lower, and you are hanging off, which you can't do on a bicycle because your outside pedal is all the way down in a turn and your inside pedal is way up in the air, much higher than a peg on a motorcycle is.

You might be able to do it if you downhilled on a BMX with the seat all the way down, which might give you enough room to hang off enough, but on a properly fitted road bike, don't think so.