How much faster is that new aero bike?

[KonaSS]

Very interesting article on Cyclingnews that attempts to address some of the questions that I have seen bantered here on the Paceline over the past few years. How much faster are the new bikes?

https://www.cyclingnews.com/features...-head-to-head/ - might be a paywall, but I was able to access in reader mode

They compared 11 new aero(ish) bikes in a windtunnel to a baseline Trek Emonda from 2015 - rim brakes, box rims, basically standard bike.

They compared with a rider on the bike at 40kph. From this they concluded that "If we're happy to accept that our baseline Trek Emonda from 2015 is representative of your generic old bike, then the savings can be anywhere between 16.65 and 32.29 watts when compared to the fastest on test. "

A bunch of other comparisons included. Lots that could be picked apart still, but does at least give an idea of the impact of the latest bikes.

[Wunder]

Paywall

[fa63]

Here is the relevant summary chart (this is with the rider on board). The difference between the Tarmac SL8 with aero cockpit / aero wheels / aero frame and Emonda ALR with aero nothing (external cables and shallow aluminum clincher wheels) was 25 Watts.

It seems that aero bikes have more or less converged (they all tested within the margin of error of the test), but if you are riding an "old-school" bike and struggling to keep up with your fast group ride, then 25 Watts is a pretty healthy savings. Or you could put an aero handlebar and aero wheels on your Emonda ALR or similar, and save about 20 of those Watts without spending $10K+ on a new bike

[fredd]

Interesting piece, 20ish watts seems to be in accordance with other sources like tour magazine. Really compelling case for modern integrated bikes for me...

[buddybikes]

Or I can go slower and "smell the roses"

[EB]

Originally Posted by fa63

Here is the relevant summary chart (this is with the rider on board). The difference between the Tarmac SL8 with aero cockpit / aero wheels / aero frame and Emonda ALR with aero nothing (external cables and shallow aluminum clincher wheels) was 25 Watts.

It seems that aero bikes have more or less converged (they all tested within the margin of error of the test), but if you are riding an "old-school" bike and struggling to keep up with your fast group ride, then 25 Watts is a pretty healthy savings. Or you could put an aero handlebar and aero wheels on your Emonda ALR or similar, and save about 20 of those Watts without spending $10K+ on a new bike

Wait - to be clear - the basis of the comparison didn't have aero wheels or an aero handlebar? And 20 of the 25 watts are from those two items? If that's the case this sounds more like an argument against modern integrated aero frames.

[fa63]

20 Watts is a rough guess, but yes, the majority of the aero gains do not come from the frame itself.

Originally Posted by EB

Wait - to be clear - the basis of the comparison didn't have aero wheels or an aero handlebar? And 20 of the 25 watts are from those two items? If that's the case this sounds more like an argument against modern integrated aero frames.

[Likes2ridefar]

Originally Posted by EB

If that's the case this sounds more like an argument against modern integrated aero frames.

Sounds about right.

[fa63]

5-10 Watts you might get from an aero frame isn't important for most people who don't race or care about going as fast as possible. But 5 W at 40 kph is 10 W at 50 kph. If it is more like 10 W at 40 kph, then it is 20 W at 50 kph. I would take 20 free Watts if I am trying to close a gap in a race or a fast group ride!

[El Chaba]

The results are pretty much what I would expect….That is, the vast majority of the savings are from aero wheels. The question I am left with is, “ They want us to tolerate internal routing for 5watts @ 40 kmph?”…..The next time I get dropped from the group ride at the local wind tunnel, I will reconsider my stand….

[fa63]

Paceline Forum doesn't represent the average bike buyer For the average buyer, it is not about the 5 Watts; it is about how clean it looks. Most of these people don't work on their own bikes either so they couldn't care less about the added difficulty of maintenance.

[sparky33]

Originally Posted by fa63

Paceline Forum doesn't represent the average bike buyer For the average buyer, it is not about the 5 Watts; it is about how clean it looks. Most of these people don't work on their own bikes either so they couldn't care less about the added difficulty of maintenance.

For sure the racing minority cares about every watt of efficiency, and they should. The reported number of watts has me wandering how much of an aero disaster my bikes are.

Your second point on aesthetics explains the popularity of sleek aero bikes for non-racers - modern aero bikes look great (to some), and for some riders that is the only priority. Who are we to judge? Well…I judge a little bit when I see someone huffing and puffing on a top-shelf race bike, as if it is their first exercise ever. It’s hard to quiet my inner snob, even though I simultaneously support all bike riding.

[benb]

What always makes me skeptical for me (and we know who these things actually matter for and who they don't) is my own ability to actually hold TT/aero positions.

If I can't hold a deeply aero position for 15-20 minutes riding hard without having to sit up to avoid a cramp, numb feet, etc.. that is the low hanging fruit for me, not how aero my wheels or frame are. Maybe my attitude would be different if I was 27 again and not 47, but my ability to hold TT position wasn't actually better back then. I had more watts available and time to train available, but I wasn't as efficient of a rider and wasn't real smart.

It's like spend $2000 on wheels, $5000-10000 on a new bike or just keep trying to figure out how I can hold a good position better, which is close to free.

Nobody ever talks about how much time you lose each time you have to sit up on the hoods cause your back is getting cramped or something. For my real world situations I think I can gain more with my position and holding a low position for long flat/downhill stretches.

I did one of these things this morning. I have a common end of ride stretch that uses part of a TT course and it's on the way back to my house so I very frequently hit segment of road at the end of rides and it's a good barometer.. can I ride tempo or threshold for that ~5 miles and hold a good aero position. I am getting closer with some recent changes but I don't think I've ever been able to ride the entire 5 miles without sitting up at some point.

I don't really have any real opinion on how often I see fully decked out aero bikes with riders sitting upright/bad position. I'm not really counting or trying to keep track, but I do think if you have a pretty upright position and you have one of those bikes it's definitely worth figuring out how to optimize your position.

Also with regard to how they used to market weight savings and now aero.. which one of these is more screwed up by the riders position or composition? Clearly the rider being overweight very quickly eclipses any amount of weight savings on the bike.. that one has always been obvious to nearly everyone, but aero is definitely more complex. At the amateur and recreational levels the whole thing of "you still save time" doesn't really matter if you're dropped. Neither the lighter bike nor the more aero bike is likely to keep you in a group that's going to drop you on a climb, and if you're hanging on the back of the pack the aero is likely not helping in the draft there. And if you get dropped on the flat the aero bike is still probably not going to let you get back on, as the aero savings are still much smaller than the savings you had when you were still in the draft of the pack.

[El Chaba]

Originally Posted by benb

What always makes me skeptical for me (and we know who these things actually matter for and who they don't) is my own ability to actually hold TT/aero positions.

If I can't hold a deeply aero position for 15-20 minutes riding hard without having to sit up to avoid a cramp, numb feet, etc.. that is the low hanging fruit for me, not how aero my wheels or frame are. Maybe my attitude would be different if I was 27 again and not 47, but my ability to hold TT position wasn't actually better back then. I had more watts available and time to train available, but I wasn't as efficient of a rider and wasn't real smart.

It's like spend $2000 on wheels, $5000-10000 on a new bike or just keep trying to figure out how I can hold a good position better, which is close to free.

Nobody ever talks about how much time you lose each time you have to sit up on the hoods cause your back is getting cramped or something. For my real world situations I think I can gain more with my position and holding a low position for long flat/downhill stretches.

I did one of these things this morning. I have a common end of ride stretch that uses part of a TT course and it's on the way back to my house so I very frequently hit segment of road at the end of rides and it's a good barometer.. can I ride tempo or threshold for that ~5 miles and hold a good aero position. I am getting closer with some recent changes but I don't think I've ever been able to ride the entire 5 miles without sitting up at some point.

I don't really have any real opinion on how often I see fully decked out aero bikes with riders sitting upright/bad position. I'm not really counting or trying to keep track, but I do think if you have a pretty upright position and you have one of those bikes it's definitely worth figuring out how to optimize your position.

Also with regard to how they used to market weight savings and now aero.. which one of these is more screwed up by the riders position or composition? Clearly the rider being overweight very quickly eclipses any amount of weight savings on the bike.. that one has always been obvious to nearly everyone, but aero is definitely more complex. At the amateur and recreational levels the whole thing of "you still save time" doesn't really matter if you're dropped. Neither the lighter bike nor the more aero bike is likely to keep you in a group that's going to drop you on a climb, and if you're hanging on the back of the pack the aero is likely not helping in the draft there. And if you get dropped on the flat the aero bike is still probably not going to let you get back on, as the aero savings are still much smaller than the savings you had when you were still in the draft of the pack.

(X) like


This is a really good post, well thought out and makes some great points…especially the last paragraph.

[bikinchris]

I would prefer to have my cables exposed and make all of my adjustments easy. I haven't been able to maintain 25mph in around 35 years.