In my 3-speed Bianchi Milano I don't know for sure how fast I was going, but I didn't spin out the day I commuted on it and rode down the longest hill. I am pretty sure I could reach my usual max I do on my commuter bike a Trek MTB with a 48 -13 as the highest gear which is plenty fast for me. So in short I think 25mph is pretty attainable on the Bianchi.