How Much Faster Are Aero Wheels?

October 5, 2019

Aero wheels don’t just look cool but we’re
also told that they make you faster too. But how much faster? We wanted to do an
experiment to see typically how much more speed an aero wheel can give you.
So to do that we came down here to Herne Hill velodrome in south London
where we are going to put three different sets of wheels to the test. So
the first set of wheels we have is a pair of Mavic Ksyrium R-SYS SLR clinchers.
We’ve picked these because they represent the typical box section
clincher wheel that you get on a normal road bike and most road bikes are
equipped with a shallow wheel like this. Second set of wheels were going to
test are a pair of Enve Smart 4.5 which have a 40mm front rim and a 50mm back rim.
Now we picked those because that’s a very classic typical current
professional set up. For the final set of wheels we’ve got a HED GT3 trispoke
front wheel and a Lighweight Autobahn Disc which is incredibly bling in about
£2500. Now we’ve picked this because it’s said to be the
ultimate time trial setup and it’s been used by the likes of Alberto Contador
amongst others. For our experiment Dr. Hutch’s going to be doing the riding.
For those unfamiliar with Dr. Hutch he’s sort of a pound shop Stig. And he’s gonna
be riding each set of wheels for 10 minutes at 200 watts and 10 minutes at
300 watts around the velodrome. We’re doing this because we thought 200 Watts
was maybe typical of a decent club rider or a sportive rider
and 300 watts is maybe more than a number a time trialist or a racer at
hit. So we’ll see what the benefit might be if you’re riding quickly and even
then what the benefit might be if you’re maybe not going quite at a race pace. For
consistency Hutch is going to begin every run from a rolling start and we’re
using Powertap P1 pedals for power measurement and we’re also using
Challenge Record tyres with latex inner tubes on all the wheels. I’ll be riding
the same Merida Reacto team bike and all the tests and keeping a consistent
position on the drops and all the tests we do to try and keep a level playing
field. Before we get on to the results, Oliver
is a proper scientist and would like to issue a quick disclaimer. Yes, so we’re
aware this is not the most accurate test in the world but for all the wind tunnel
data that exists around bikes and wheels no one actually rides their bike in a
wind tunnel. I do. Apart from Hutch. So based on that we want to see what
actually happens when you ride these things outside so there is value in that
and Herne Hill is about as much as a controlled environment as you can get
outside. So, Oliver, what were the results? The Mavics that you rode first at 200
watts you travelled the distance of 5120m,
an average speed of 30.7 km/h and at 300 watts you traveled 6070m at an average speed of 36.4km/h. So quite a
bit faster faster – yeah, yeah. So then on to the Enves you travelled at 200 watts
5460m at an average speed of 32.7km/h. So that’s two and a bit kilometres an hour faster? A two kilometers an hour faster. And at 300 watts you travelled 6442m at an average speed of 38.6km/h. So again roughly two kilometres an hour
faster. So for the super-duper TT set up at 200 watts you travelled 5520m, an average speed 33.12km/h.
And at 300 watts… Little quicker… Yeah, a little bit quicker. And at
300 watts you traveled 6600m at 39.6km/h. So that’s basically
25 miles an hour. And that’s quicker again. Yeah, so just a little bit
quicker than the Enves but I think the main thing is the difference between the
Enves and the time trial wheels were quite small. So the big
step up is from the kind of box section simple shallow rim wheels up to the
modern rim wheels. Yeah and even at 200 watts you’re traveling 2km/h faster on a 40/50mm rim.
And it’s actually quite windy here today so you know with
the kind of your angles and the rest of it actually deep rims probably start
to perform even better. But it does go to show that I mean even if you’re just
averaging 200 watts over the course of a 100 miles sportive that could really
add up to a massive. If you’re spending 5 or 6 hours out it’s going to be most of another hour’s work. So if saving two
kilometres an hour is important to you then investing in some aero wheels is well
worth considering. How much you care about two kilometres an hour Oliver? I’ve
killed for two kilometres an hour.

Leave a Reply

Your email address will not be published. Required fields are marked *