Technical FAQ: Droppers post for an aero advantage, more on synthetic materials and skin sensitivity

Mountain bike tech could offer a UCI-legal solution to improving aero positions on road bikes; more discussion about skin sensitivity, allergies, and irritations when wearing cycling shorts.

Photo: Kristen Legan |

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Have a question for Lennard? Please email him at to be included in Technical FAQ.

Dear Lennard,
With the recent banning of the super tuck, do you think there’s any chance we’ll see roadies using dropper posts to gain an aero advantage? As far as I know, they are UCI-legal. I’ve noticed on my road rides to the trailhead I go a lot faster on my mountain bike if I drop my saddle. And I only get into the mid-30s (kph). At road race descending speeds, I would think a dropper would give almost as much advantage as the super tuck, but I’m not aware of any testing to confirm or deny this.
— Rob

Dear Rob,
I’m certain it would be faster to drop the seat down and tuck than to tuck while sitting at normal seat height. If I were a road pro right now, I would certainly put a dropper post on my bike for a race with big descents. Many bikes in the pro peloton have some extra weight to add to get up to the UCI weight minimum anyway; this could be a very good use of that.
― Lennard

Dear Readers,
Last week’s column featured a question from a reader named Tom about skin sensitivity to stretch fabrics used in cycling. I received a lot of mail about it containing many suggestions that are included below. First, to that original question, we again have a very thorough answer from Hugh Walton, a former pro rider who racked up countless victories in the USA and Canada; for decades, he headed up some of the world’s finest cycling apparel brands, including Pearl Izumi and Descente and is currently the general manager of CCNSport-USA, Inc.

He addresses each of Tom’s points separately.
― Lennard

Tom says:
After decades of avid bicycle racing and training, I have developed a sensitivity to many synthetic fabrics.

Hugh Walton responds:
Tom uses the exact correct term. Often what is mistaken for an “allergy” is skin sensitivity. There are very few true allergies to synthetic fibers, namely: polyester. There are no known allergies to the world’s first synthetic textile fiber, “rayon,” 1911 [ed. note: rayon was developed in 1899 and was first produced commercially in 1905].

Tom says:
It’s not the chamois, it’s the stretchy stuff.

Hugh Walton responds:
There are very few known true allergies to Spandex, the fiber/yarn that makes our cycling clothing stretchy. Spandex is made from polyurethane. There are rare cases of contact dermatitis from polyurethane, quite rare but real; not strictly an allergy, but a “sensitivity.”

Tom asks:
Do any of the top cycling apparel makers specialize in gear for this issue?

Hugh Walton responds:
Not that I am aware of.

Tom says:
I do wear wool whenever possible but have yet to find any high-quality wool/hypoallergenic shorts suitable for long days in the saddle.

Always machine wash your brand-new cycling garments in warm water, gentle mode, with detergent, before wearing. Tumble dry low; that’s 100 percent okay. Photo: Lennard Zinn |

Hugh Walton responds:
The most common fabric for bike shorts: nylon/Spandex, or for printed bike shorts: Spandex/polyester. Wool was long considered to be an allergen, but that claim has been refuted. Ultra-fine merino yarns are made of <18 nm fibers; some folks suffering from eczema sometimes take refuge in merino wool garments. The merino wool bike shorts I’ve seen have a small component of Spandex to make them stretchier and more durable.

Tom says:
Perhaps your contacts in the industry know more than Google on this topic.

Hugh Walton responds:
I am speaking from 40 years of textiles experience; thank you for your consideration.

Lastly, sometimes people react to the cleaning chemicals used on textiles in the finishing process, such as chloroform. However, to my knowledge, there are no known allergies to silicone, which is the earth’s second most abundant element (ed.: silicon is the second most abundant element on earth, whereas silicone is a synthetic polymer that contains silicon). There are some known cases of contact dermatitis to silicone grippers: sweating, redness. I’ve experienced this myself, especially on hot days with lots of sweating.

Always machine wash your brand-new cycling garments in warm water, gentle mode, with detergent, before wearing. Tumble dry low; that’s 100 percent okay. Leg shaving can reduce irritation from constrictive cycling clothing.

Spandex-Lycra was invented by DuPont in the 1950s; there are a few stretch polyester yarns on the market. Indoor cycling is associated with higher levels of skin irritation (contact dermatitis) due to excessive sweating indoors.
— Hugh Walton, general manager, CCNSport-USA, Inc.

Dear Lennard,
I spent 20 years as the customer service manager for one of the largest cycling apparel companies in the US, and every once in a while, I’d speak to a consumer who thought they were having an allergic reaction to one of our products. I always asked them to perform the same test: wear your kit for a couple of hours while sitting on the sofa. If you get the rash, then you may indeed be experiencing a true allergic reaction. If you don’t get the rash while sitting on the sofa, then it’s more likely a heat rash or enhanced skin sensitivity that’s aggravated by vasodilation and/or friction against the fabric itself (bike shorts should be pretty darn tight, and I see lots of people wearing saggy shorts). Unfortunately, I never had anyone who followed up with me, but I assume that if they were actually allergic to our fabric, they would have said something.
— Jeremy

Dear Lennard,
I have followed the discussion on chamois and fabric sensitivity and have a couple of suggestions.

The man who is sensitive to the fabric of his kit may be sensitive to his laundry soap. I had developed some rashes long ago and switched to Woolite. That worked for me.

As for chamois and saddle interaction, I follow the advice I received from old-time friends and fellow ultra riders, Ed Pavelka and Fred Matheny. I use Lubriderm. Drew is right about petroleum products. The Lubriderm is a thick substance that loosens up from the heat your body generates to provide long-time protection and also has an antibiotic to help with infections. It works really well on my summer, desert rides.
— Steve

Dear Lennard,
Crotch Guard is an alternative to greasy chamois creams. It has worked well for me for a number of years. Another possibility is coconut oil. It’s cheap and available at most groceries. It’s actually recommended for use as a personal lubricant by my wife’s gynecologist.
— Charles

Dear Lennard,
While I don’t come close to the mileage mentioned by Tom in your current lead letter, I’ve had good luck using corn starch (baking section at the grocery — very low cost). Perhaps this, or another “solid lubricant” powder would provide enough of a barrier to separate his skin from the elastic material(s) that he seems to have become allergic to?

Another thought for long indoor rides would be to take a short break in the middle [of the ride], wash and pat dry, and then start with fresh lube and fresh shorts?
— Doug

Dear Lennard,
As for shorts, yes, I’ve found an excellent supplier in Italy. They produce a variety of vintage jerseys, shorts, shoes, helmets, etc. in house. I met them at L’Eroica a couple of years ago, and I’ve purchased a few jerseys and I did a custom order of jerseys and shorts from them this past year. The wool shorts are very comfortable, and they use a modern chamois pad. To be honest, I’ve not done any huge rides on them (nothing more than a couple of hours), but I’m quite certain that they would be as comfortable as a good modern short: Tiralento is the company name. They make the fabrics in house (or possibly in partnership with a supplier) on legacy machines.

The thing with wool shorts is that you have to adjust your expectations with respect to fit. Lycra bibs, when fit properly, don’t move around — which is a good thing — since the relative motion between your skin and the pad or seams is often what leads to irritation. Wool shorts ride up on the leg (I’m sure you remember!) Check out any photo of Mr. Merckx from back in the day, and the shorts are definitely not down to his knees. But having said that, as long as you’re using suspenders to hold everything in place, it’s not uncomfortable at all. The only thing you need to be aware of is you’ll need some sunscreen if you’ve got a traditional biker tan, and you switch to wool.

There’s also a supplier out of Serbia selling decent wool jerseys. They also sell wool shorts with a traditional “old school” leather chamois. I’ve not purchased a pair of those yet, but I probably will. I bought a jersey from them, and it was nice. Not as high quality as the Tiralento products, but acceptable for the price. Also, I know of another supplier in Italy who supplies custom to most of the vintage clubs in Italy. I’ve seen that stuff but don’t own any of it.

Anyway, sorry for the long-winded reply, but this retro stuff is definitely my jam.
Henrik Nezechleb, CEO, Pandana USA

Dear Lennard,
In your recent Technical FAQ article, I read about Tom’s allergy to spandex. For anyone searching for merino wool cycling apparel, there is one company that makes cycling bibs that are of high-quality Australian merino wool. They are Breathe Velo in Tasmania, and their bibs feature a shoulder brace and certain panels in merino. The chamois in these bibs are also synthetic, and the company offers more sizes than many other brands. Since wool is not as stretch-resistant as synthetic materials, certain high-stress panels are sewn to wool panels to make a comfortable, durable bib.
— Marc

Dear Lennard,
I read the issues from the guy who has skin problems with synthetic materials and was gonna suggest Nalini’s 70s bib short, but it looks like they don’t make ’em anymore. My wife wears the Nalini wool bibs and knickers, not only on vintage bikes, and she likes them quite a lot.

These people make some great stuff, and I’ve met the owner a time or two, so next time I need some wool bibs for L’Eroica style cycling I’ll give them a try. They make the GIOS clothing, which I know is good quality.
— Larry

Lennard Zinn, our longtime technical writer, joined VeloNews in 1987. He is also a custom frame builder ( and purveyor of non-custom huge bikes (, a former U.S. national team rider, co-author of The Haywire Heart,” and author of many bicycle books including Zinn and the Art of Road Bike Maintenance,”DVD, as well as Zinn and the Art of Triathlon Bikesand Zinn’s Cycling Primer: Maintenance Tips and Skill Building for Cyclists.” He holds a bachelor’s in physics from Colorado College.

Follow @lennardzinn on Twitter.

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