There's also the issue of saddle set-back. The rule of thumb is that, when the pedals are horizontal, your knee (well, the bit just behind the knee cap) should be over the pedal's axle. As with much of the lore of the mechanics of cycling, it's very dependant on your pedalling technique, the type of bike etc. However, it might be worth giving that a few seconds to check as well, whilst you are playing with the other stuff.