Aerodynamics in Cycle Touring - If You Care

Cycle-touring, Expeditions, Adventures, Major cycle routes NOT LeJoG (see other special board)
simonhill
Posts: 5226
Joined: 13 Jan 2007, 11:28am
Location: Essex

Aerodynamics in Cycle Touring - If You Care

Post by simonhill »

People may be interested in this article. Basically drag of various types of luggage, position and clothes. Not a complete study, but some thought provoking stuff, if you want to shave some time or effort off your days in the saddle.

As for me, I won't be changing anything, but I now know I can blame my rear panniers for my 'relaxed' speed.

https://www.cyclingabout.com/fascinatin ... e-touring/
Jdsk
Posts: 24636
Joined: 5 Mar 2019, 5:42pm

Re: Aerodynamics in Cycle Touring - If You Care

Post by Jdsk »

Very interesting.

Thanks for posting.

Jonathan
User avatar
horizon
Posts: 11275
Joined: 9 Jan 2007, 11:24am
Location: Cornwall

Re: Aerodynamics in Cycle Touring - If You Care

Post by horizon »

He also did an analysis of the effect of weight (which we discussed on here some while back). This is his intro:
Before I started this testing, I felt that the effects of weight were blown out of proportion. Some people spend huge amounts of money on lightweight bikes and gear with the idea that it will make their tours easier or faster. Some people even leave gear at home that can significantly improve the comfort of their bike trip.
The idea behind this testing is to quantify weight into time. That way we can be more rational about our gear choices!
This was his conclusion:
A little bit of extra weight isn’t that significant in terms of time.
A handful of kilograms is not going to impact your tour significantly. It will add a few minutes to your daily ride time only.
I haven't read your link yet so I'm interested to see if he comes to the same conclusion about aerodynamics but I think he believes wind resistance to be much more important than weight.

Personally I just lower the gears!
When the pestilence strikes from the East, go far and breathe the cold air deeply. Ignore the sage, stay not indoors. Ho Ri Zon 12th Century Chinese philosopher
User avatar
simonineaston
Posts: 8003
Joined: 9 May 2007, 1:06pm
Location: ...at a cricket ground

Re: Aerodynamics in Cycle Touring - If You Care

Post by simonineaston »

Folks interested in applying aerodynamic principles to cycle touring might recall that the launch of Moulton's spaceframe in the guise of the AM model attracted a modest range of accessories taking advantage of the design. These included a fairing sold as the Zzipper, which appears to be still available for most cycle frame designs - see here.
And although touring it is clearly not, the fully-faired AM developed by Doug Milliken and ridden by Jim Glover, took the World Speed Record for a cycle ridden in the conventional postion in 1985 and again in 1986 - a record which still stands - see here. The message appears to be that fairings clearly do work if you want to hurry along. However, half the point of touring by bike for me, I think, is just being able to potter.
S
(on the look out for Armageddon, on board a Brompton nano & ever-changing Moultons)
NickJP
Posts: 797
Joined: 24 Sep 2018, 7:11pm
Location: Canberra, OZ

Re: Aerodynamics in Cycle Touring - If You Care

Post by NickJP »

Back in the 1980s I used a ZZipper fairing for a while (it eventually got stolen). I found the biggest advantage was when riding in temperatures below freezing in winter - the fairing made a big difference in minimising the windchill. Here it is on our tandem on a winter ride somewhere in the NSW Southern Highlands:
Scan-110321-0053.jpg
And here's some largely home-made over-the-top streamlining from the same era. Besides the obvious streamlining, note the back-to-front mudguard over the front wheel and the faired DT and derailleur. It worked, too - I was able to chop about six minutes off my 40km TT time on that machine vs the standard drop bar road bike of the time. You could only take that setup out on absolutely still mornings, though. Even a fairly gentle sidewind made the bike quite dangerous to ride.
Scan-120904-0002.jpg
ClappedOut
Posts: 585
Joined: 30 May 2020, 12:43am

Re: Aerodynamics in Cycle Touring - If You Care

Post by ClappedOut »

NickJP wrote: 14 May 2021, 9:28am Back in the 1980s I used a ZZipper fairing for a while (it eventually got stolen). I found the biggest advantage was when riding in temperatures below freezing in winter - the fairing made a big difference in minimising the windchill. Here it is on our tandem on a winter ride somewhere in the NSW Southern Highlands:
Scan-110321-0053.jpg

And here's some largely home-made over-the-top streamlining from the same era. Besides the obvious streamlining, note the back-to-front mudguard over the front wheel and the faired DT and derailleur. It worked, too - I was able to chop about six minutes off my 40km TT time on that machine vs the standard drop bar road bike of the time. You could only take that setup out on absolutely still mornings, though. Even a fairly gentle sidewind made the bike quite dangerous to ride.
Scan-120904-0002.jpg
Is the aero frame tubular aluminium and a silly question but the fabric stretched over it is lycra type or similar?
mattheus
Posts: 5044
Joined: 29 Dec 2008, 12:57pm
Location: Western Europe

Re: Aerodynamics in Cycle Touring - If You Care

Post by mattheus »

NickJP wrote: 14 May 2021, 9:28am Back in the 1980s I used a ZZipper fairing for a while (it eventually got stolen). I found the biggest advantage was when riding in temperatures below freezing in winter - the fairing made a big difference in minimising the windchill. Here it is on our tandem on a winter ride somewhere in the NSW Southern Highlands:
Scan-110321-0053.jpg

And here's some largely home-made over-the-top streamlining from the same era. Besides the obvious streamlining, note the back-to-front mudguard over the front wheel and the faired DT and derailleur. It worked, too - I was able to chop about six minutes off my 40km TT time on that machine vs the standard drop bar road bike of the time. You could only take that setup out on absolutely still mornings, though. Even a fairly gentle sidewind made the bike quite dangerous to ride.
Scan-120904-0002.jpg
Fantastic - the kind of post that makes this forum worthwhile!
I'm really not surprised by the windchill benefits, it's something I've long pondered.

(Did they let you race that machine? I'm pretty sure it breaks CTT rules but I couldn't quote the exact reg. Either way, a great experiment! )
User avatar
squeaker
Posts: 4112
Joined: 12 Jan 2007, 11:43pm
Location: Sussex

Re: Aerodynamics in Cycle Touring - If You Care

Post by squeaker »

simonhill wrote: 13 May 2021, 7:37pm People may be interested in this article. Basically drag of various types of luggage, position and clothes. Not a complete study, but some thought provoking stuff, if you want to shave some time or effort off your days in the saddle.

As for me, I won't be changing anything, but I now know I can blame my rear panniers for my 'relaxed' speed.

https://www.cyclingabout.com/fascinatin ... e-touring/
Like the punchline 8)
Or alternatively, we could all just ride aerodynamically-superior recumbent bicycles.
"42"
m-gineering
Posts: 254
Joined: 23 May 2015, 12:01pm

Re: Aerodynamics in Cycle Touring - If You Care

Post by m-gineering »

mattheus wrote: 14 May 2021, 10:15am I'm really not surprised by the windchill benefits, it's something I've long pondered.
The opposite was also true, I remember very hot hands in hot weather .

And streamline in a headwind is one thing, but how the rig reacts to sidegusts or wind coming in at an angle is also important. Sailing along with a push from behind is nice, having a fight trying to keep to a line with every passing truck not so much
Marten

Touring advice for NL: www.m-gineering.nl/touringg.htm
Psamathe
Posts: 17650
Joined: 10 Jan 2014, 8:56pm

Re: Aerodynamics in Cycle Touring - If You Care

Post by Psamathe »

The baggy clothes (5% slower) is a surprise but in warmer places I find the air movement effect of baggy clothes a great benefit (something I'd accept 5% on). Of course there are degrees of baggy clothes and I tend to wear lycra shorts and a baggy polo shirt which would probably be a lower impact than e.g. baggy jeans and baggy long sleeved sweatshirt.

Ian
willem jongman
Posts: 2750
Joined: 7 Jan 2008, 4:16pm

Re: Aerodynamics in Cycle Touring - If You Care

Post by willem jongman »

The results are interesting, but a bit crude I think. For me, apart from avoiding baggy clothes, it still begins with a reduction in what you take: reduce weight and volume of your luggage at the same time. It is also clear that large panniers are a bad idea, and that is in fact something you notice when you ride into the wind. However, if you reduce your luggage enough, small front or rear panniers will be enough, and I would bet that with their smaller front area they are far more aerodynamic than large ones. And the benefit from a narrow saddle bag is unlikely to be very different from that of a small tent along the length of the top of a rear rack. And notice that a bar bag and mudguards impose no meaningful drag penalty.
pq
Posts: 1294
Joined: 12 Nov 2007, 11:41pm
Location: St Antonin Noble Val, France
Contact:

Re: Aerodynamics in Cycle Touring - If You Care

Post by pq »

It's an interesting article, and not one I thought I'd ever see. For me the issue is not aerodynamics in normal conditions (I don't care about that, it's not significant enough), it's when you have to ride for day after day into a howling headwind, which I've done quite a few times. Whilst labouring at barely walking speed I've looked down at my front panniers (usually rears mounted on front low riders) and wondered how much difference the extra frontal area was making - it seems quite a lot. But I've tried bikepacking bags and frankly in most situations I'd rather put up with the aerodynamic losses than those bags. What is nice to read is that the normal racing gear I wear when touring is making life easier - I only wear baggy gear when lycra would offend local sensibilities.
One link to your website is enough. G
mattheus
Posts: 5044
Joined: 29 Dec 2008, 12:57pm
Location: Western Europe

Re: Aerodynamics in Cycle Touring - If You Care

Post by mattheus »

PQ / Willem agree with both your posts!
NickJP
Posts: 797
Joined: 24 Sep 2018, 7:11pm
Location: Canberra, OZ

Re: Aerodynamics in Cycle Touring - If You Care

Post by NickJP »

mattheus wrote: 14 May 2021, 10:15am(Did they let you race that machine? I'm pretty sure it breaks CTT rules but I couldn't quote the exact reg. Either way, a great experiment! )
Never tried to ride it in an actual organised TT - just took it out on a TT course that I'd ridden several times previously to see what difference it made.
m-gineering
Posts: 254
Joined: 23 May 2015, 12:01pm

Re: Aerodynamics in Cycle Touring - If You Care

Post by m-gineering »

mattheus wrote: 14 May 2021, 10:15am (Did they let you race that machine? I'm pretty sure it breaks CTT rules
It was legal in HPV races, but did upset a lot of people ;)
Marten

Touring advice for NL: www.m-gineering.nl/touringg.htm
Post Reply