Originally Posted by
Doge
They will make a significant difference over just being in the drops for two reasons. They get your arms inside as a wind break to your body instead of being outside your body and likely get your torso lower than you would be comfortable riding in drops bending your elbows. The angle between your torso and legs is not more acute and you have a smaller total profile facing the wind.
Now the down side...
This may affect your fit/comfort on the bike. Your power may be lower. This position would normally call for the seat being moved forward and higher.
If you are experienced at riding with forearms on the bar tops (I assume you are not) there would be little difference except in the large power sections where you can pull against the clip-on.
If that 2% is going to keep you much under 20mph, you may want to sacrifice the aero and go for comfort and power, however as it is out and back I assume your have some speed on the 2% decent. Aero always matters, just more as speeds get higher.
In my experience, yes. Even without changing anything else (no seat/stem adjustments), I'm noticeably faster with clip-ons.
Thanks. I think I'm going to try and set it up without adjusting my saddle position and see if I can get decently comfortable. I have a road race later that day, so I don't want to jack things up too much. Average speed will definitely be over 20 mph, but there will probably be several gear changes desired with the rollers and high wattage on a shorter time trial.