I’m considering putting some clip-on aerobars on my road bike and was curious on how much time these might actually save me in an IM distance race.
I loaded my stats into best bike split and compared times for a relatively flat IM (Kalmar) bike-split with three ‘racing positions’:
Drops
This setting is reserved mostly for those racing on road bikes in short time trials where an athlete will stay in the drops. It is possible for the drag to be better in the drops than on a triathlon or time trial bike depending on the athlete.
Aerobars (Recreational Triathlete)
This setting is for those who have very little flexibility and use the aerobar more for long distance support. On a Tri Bike if your bars are at or a bit above your seat this may be a good setting for you. Consequently you could also measure your Torso Angle and if it falls in a 45+ degrees range this would be a setting to start with.
Aerobars (Midpack Triathlete)
If you are not very flexible and have a fairly upright position this is a good starting setting. If you are using clip on bars you may want to start with this setting as well.
With ‘racing position’ defined as: The position that you spend the majority of a race in
The results surprised me:
I’m wondering how common, and what are the conditions that riding on the drops seems to be more aero than in two reasonable aerobar positions. BBS even mentions that drag may be lower on the drops than on TT bike, however I’ve never heard this brought up in the general drops vs aero discussions and it seems such common knowledge that slapping on aero bars is an easy aero win, all else equal. I’m wondering if this is a common tradeoff.
I.e. Is it common to accept less aero positioning on aerobars in exchange for not having to waste the muscular energy trying to stay in the drops for the majority of 112mi (is staying in the drops for 112mi even a thing)?
I can’t imagine how crappy an aerobar setup you would need to be in order for it to be slower than riding in the drops because in the drops your arms are outside of the knees. Even a wide aerobar stance has your elbows aligned with the knees. This makes your frontal area smaller on aerobars.
I’m pretty sure that “drops” means forearms close to parallel in the drops. Not sure many people who can hold that position for 180km. If you have a position on the drops where your elbows are straight or near straight then your bars are too low.
Clip on aero bars usually do not give a good aero position. Just a better position than on the hoods because of the stack height of mounting them on top of the bars. To get a fairly good position on a road bike you have to consider adjusting the bars and lowering them so the position of the clip ons is what you can hold for the race.
one option is to use and adjustable stem and try out various positions. also helps to have clip ons with a fair bit of fore/aft adjustment.
Clip on aero bars usually do not give a good aero position. Just a better position than on the hoods because of the stack height of mounting them on top of the bars. To get a fairly good position on a road bike you have to consider adjusting the bars and lowering them so the position of the clip ons is what you can hold for the race.
one option is to use and adjustable stem and try out various positions. also helps to have clip ons with a fair bit of fore/aft adjustment.
I think this is the most logical take away. It surprised me because I hadn’t heard it discussed before and the popular data (I’ve seen) tends to not to reflect this.
Tests have shown that having your hands on the top of the of the brakes and having your forearms parallel to the ground is more aero than having your arms in the drops. Having your arms in the drops and parallel to the ground is not something that you are going to be able to hold for a long time so having your arms in the drops and angled back at a 45° degree angle is not going to be faster.
Aerobars if done right and with a very low stack height should be more aero than your drop position and most likely fairly close to having your arms on the top of the brakes and parallel to the ground.
Will waiting for someone to design a pair of drop bars with integrated extensions with a zero stack height. a nice aero drop bar with extensions. It could be done with something coming off the stem that bolts one with the extensions directly in front of the stem or something more creative. Just not a huge market really.
I can’t imagine how crappy an aerobar setup you would need to be in order for it to be slower than riding in the drops because in the drops your arms are outside of the knees. Even a wide aerobar stance has your elbows aligned with the knees. This makes your frontal area smaller on aerobars.
^^^^^This.
For any given athlete, their best sustainable aero bar position will be MUCH faster than their best drops position. This is why no serious triathlete or cyclist uses a drops position for a TT (uphill TTs being a possible exception). A great drops position might beat a horrible aerobar position…but why would an athlete with the flexibility and core to hold a great drops position not have a better aero one?
Tests have shown that having your hands on the top of the of the brakes and having your forearms parallel to the ground is more aero than having your arms in the drops. Having your arms in the drops and parallel to the ground is not something that you are going to be able to hold for a long time so having your arms in the drops and angled back at a 45° degree angle is not going to be faster.
While this is common nowadays, it is not a universal law and doesn’t apply to everyone.
It’s primarily the result of the bike fit trend of having road bike bars too low. In general that is.
Of the pros I have aero tested, being on the hoods is typically the best aero, while those pros with more old school sets up are more aero (and sustainably so) while riding in the drops. That’s not to say the newer fit trend is bad but I do wonder sometimes why it’s gone that way.
I was expecting this post to be accompanied by a picture of some guy riding with clip-ons higher than his seat and his back at about 60 degrees
I’m certainly quicker in the drops than on clip-ons, for the simple reason that all else being equal the drops position gets my body a lot lower. I.e. if my road bike is fit well, I’d have a horizontal stem with no spacers, and a drops position that allows me to get my back horizontal when I’m down there with bent arms. Stick a pair of clip-ons on top of that bar and I’m significantly higher, the only way I could get horizontal would be have a really stretched out position which is going to compromise my power, or dropping my bars using a negative stem, which would screw up my hoods and drops position.
Problem with the drops position is that your weight is supported muscularly instead of skeletally which is the case with aerobars. So it leads to a lot of tension in your back, shoulder and arm muscles which either means it’s not sustainable for a long bike leg, or at least if you can sustain it you’re not going to be in great shape to run.
Problem with the drops position is that your weight is supported muscularly instead of skeletally which is the case with aerobars. So it leads to a lot of tension in your back, shoulder and arm muscles which either means it’s not sustainable for a long bike leg, or at least if you can sustain it you’re not going to be in great shape to run.
Only if your bike fit is poor.
The amount of weight borne by the hands while on a road racing bike should be fairly minimal. Indeed you should be being able to relax the hands and all but be able to lift them a few mm off the bars and ride along in position without much trouble.
Problem with the drops position is that your weight is supported muscularly instead of skeletally which is the case with aerobars. So it leads to a lot of tension in your back, shoulder and arm muscles which either means it’s not sustainable for a long bike leg, or at least if you can sustain it you’re not going to be in great shape to run.
Only if your bike fit is poor.
The amount of weight borne by the hands while on a road racing bike should be fairly minimal. Indeed you should be being able to relax the hands and all but be able to lift them a few mm off the bars and ride along in position without much trouble.
i took the liberty of lifting, and posting here, a picture (of you?) from your coaching site.
i’m pretty sure what what you say is true if the image is emblematic of how you actually ride (there is always a limit to how much you can glean from a picture).
if you ride the way most triathletes ride, what you say is NOT true, that is, what you say about road racing is true (not too much weight on the hands) but the weight on the hands would be SIGNIFICANT if you put yourself in the position most triathletes ride in and then took away the aero bars and held yourself up by your hands.
i guess my point is, if that’s a picture of a TT set up you admire i can see why a road set up hands on the hoods or drops would be no slower. both are quite rearward. you lose most of the advantage of aerobars if you ride a bike with aerobars that way.
i guess my point is, if that’s a picture of a TT set up you admire i can see why a road set up hands on the hoods or drops would be no slower. both are quite rearward. you lose most of the advantage of aerobars if you ride a bike with aerobars that way.
A strawman Slowman.
More specifically I don’t even know who it is, let alone paid any attention to the position of the rider nor formed a view on whether or not I admire it. Ric Stern might know who it is if you wish to have a chat with them about their bike position.
