Talk:Jotaro VS Kenshiro/@comment-31165581-20180304132251/@comment-32295718-20180304142449

There comes a point where you can't accurately measure speed anymore. Humans are not that great at guessing speed with just their eyes. Josuke could have simply guessed that it's about 300 km/h because he saw his stand outrace something at that speed, but it wasn't even nearly the fasted speed it could have gone.

If you have a guidebook which states something, and actual feats in the series that back it up, then the statement can be assumed legit.