I just bought one of these,my first bike since 1975.My last ride was a 1946 wla,45 c.i. flathead which was capable(theoretically)of 23.6 HP.This thing will gin up 45.If I remember correctly,a stock Panhead would be in the forties HP wise.I gurantee you that the top end of a Shadow 750 is far in excess of what any of us should even consider doing.