Originally Posted by
mack_turtle
sorry, but what does COA mean? not familiar with that term as it relates to bicycles.
I am not sure whether it's preferable to use a longer or shorter stem, or if at what point it matters. how short is too short for handling on a road-going bike? too long? that might be a bit subjective. it's also possible that a stem length outside of the norm on a conventional road bike is an indication that the rider chose a bike of the wrong size. in my case, I think I could make either of these bikes fit with a 70-100mm stem because the two sizes are not dramatically different.
COA - Course of Action
Just a general rule of thumb for a Road Bike...I see you are going for an endurance/all rounder...so this may not apply. After purchasing the correct size frame (road bike) and your position is fine tuned...the stem should be between 100mm - 120mm. The idea is if you require a 130mm stem, the frame is most likely too small (should go with the next size up). If you require a stem 90mm or below, the frame is most likely too big (and you should go with the next size down).