Water — A Very Cool Story!

As I stated in my last post, water is my favorite inorganic molecule! It is so simple, yet it has extremely unique properties. For example, as you well know, ice floats in liquid water. However, that’s not the case for the solid vs. liquid forms of most substances, inorganic or organic. Why’s that? Well, it goes back to the physical property of density. The density of solid ice is less than that of liquid water because the amount of molecules that are “packed” into a certain amount of space is less for ice than for liquid water; that makes ice less dense, and it floats. (Thank goodness, as there would otherwise be no ice-skating on frozen lakes and ponds in the winter.)

But that’s enough about ice; brrr! We don’t want our motorcycles’ engines to be quite that cold, but we do want them to be kept cool so that they don’t overheat while we are at idle or while touring, commuting, racing, etc.

In general, engine cooling occurs in one of two ways, air or liquid cooling. The vast majority of modern sport and race bikes are liquid cooled, with the most common liquid being (you guessed it) water!   (Well, it’s not usually pure water, but we’ll touch on that shortly.) There can be some disadvantages to water-cooled engines. In brief, there are more parts to leak or fail, such as hoses and water pumps that are needed to keep the water circulating around the outside of the cylinders and cylinder heads (in the “water jacket”). Nevertheless, water is plentiful and it has another fabulous physical property that is unique in comparison to other similar molecules. It has a very high specific heat capacity.

A high what? It’s okay if you aren’t familiar with this term. It’s fairly simple to understand. Specific heat capacity is how much heat energy a substance must absorb to raise one gram of that substance by a single degree Celsius. Looked at another way, if a substance has a high specific heat capacity, then a one degree temperature change results in more heat being absorbed for the same amount of material, compared to a substance with a low specific heat capacity. For example, it takes about four times as much heat energy to raise the temperature of a gram of water from 20-21°C (or from 45-46°C), as it does to effect that temperature change for a gram of aluminum or air. Aha! While air has the advantage of being all around your engine, it can’t absorb the amount of heat energy that water can to keep your engine within a safe operating temperature. And air only circulates if you are in motion or it’s windy. That’s not so great out in the desert as you are idling and waiting for your rally race to begin.

Speaking of desert riding, there are both hot and cold temperature extremes in which even our fantastic water molecule can’t do its job. At 100°C, water boils and at 0°C, it becomes ice. So, that’s where anti-freeze comes in handy. In fact, anti-freeze (often, but not always, the compound ethylene glycol) when mixed with water actually lowers the freezing point and raises the boiling point. That’s a pretty “cool” effect. The chemistry behind these physical changes of the properties of the mixture compared to pure water has to do with the general principal of “colligative” properties of substances.

[You can learn more about that at the HyperPhysics site,


When I asked my husband why it took him almost 30 years before he owned a water-cooled bike, the answer was basically due to the simplicity of the air-cooled engines. In fact, his first water-cooled motorcycle had a water pump failure while we were riding California’s Highway 9 through the Santa Cruz Mountains. So, why did he encourage me to purchase a water-cooled motorcycle as my second ride?

Well, I wanted more horsepower for street riding, which meant that I needed an engine with either a greater displacement or one of similar displacement that could run a higher compression ratio. I chose the latter, and that required it to be water-cooled, due to the higher engine operating temperature. I was happy. I had a bike with similar size and weight, but I could get more “bang for the buck”.

It’s still true that air-cooled engines are simpler to maintain if you are a do-it-yourself kind of person. But if you have a good mechanic, or your own shop, then why not give water-cooling a try?

Speaking of mechanics, my next post will feature a guest co-host and former student of mine who is a certified motorcycle mechanic. We’ll be talking brake pads. Oh, stop!

Carbon Fiber: Strong, Light and “Organic”?

Carbon fiber has been used in many applications because of several of its important features such as its strength and lightness. Those characteristics will be explored in this post but the chemist in me must first address the nature of carbon and carbon containing compounds.

The term “organic” has most likely become familiar to many of you because of its connection to foods – how foods are farmed, processed, preserved, etc. However, to a chemist, the term organic means the branch of chemistry that involves the study of compounds that contain the element carbon.

My inorganic chemistry colleagues will be the first to remind me that carbon, in its pure form, is not actually considered to be organic because it’s an element, not a compound. Pure carbon takes several forms, including the “lead” in your pencil (graphite form), a lustrous gemstone (diamond form) and some other forms that have been discovered within the past century, such as the fullerenes (usually 60-70 carbon atoms arranged in a 3-D structure similar to a soccer ball or geodesic dome, thus, affectionately known as “Bucky balls” after Buckminster Fuller).

So, is carbon fiber organic? The answer is — it depends on the context! The website “How Products are Made” (http://www.madehow.com/Volume-4/Carbon-Fiber.html) explains the composition of and process for making carbon fiber, as follows:

“A carbon fiber is a long, thin strand of material about 0.0002-0.0004 in (0.005-0.010 mm) in diameter and composed mostly of carbon atoms. The carbon atoms are bonded together in microscopic crystals that are more or less aligned parallel to the long axis of the fiber. The crystal alignment makes the fiber incredibly strong for its size. Several thousand carbon fibers are twisted together to form a yarn, which may be used by itself or woven into a fabric. The yarn or fabric is combined with epoxy and wound or molded into shape to form various composite materials.”

Aha! So basically carbon fiber alone is probably best classified as inorganic but those “composite materials” are carbon based compounds (plastics, epoxies, etc.) and are thus classified as organic. Therefore, if you have carbon fiber composite “bits” on your motorcycle, then you can make the claim that your bike is (at least partly) organic! (Try dropping that line while shopping at your local organic food co-op and let me know about the reactions you get!)

OK – back to the matter at hand … so, it’s the way that the fibers are aligned that gives carbon fiber its characteristic strength. This strength, combined with its light “weight” makes it a very desirable material in the manufacture of automobiles and motorcycles, especially in racing applications where both strength and lightness are highly desirable. It is very important to note that carbon fiber and carbon fiber composites have complex characteristics that require multiple measures for comparison with other materials. However, to simplify the issue of lightness, one can compare the simple physical property of the density (the mass per unit volume) of the materials. Steel has a density that is a little more than five times that of a typical carbon fiber composite, and aluminum’s density is almost twice that of such a composite. The bottom line, then, is that the same sized (volume) part made from a carbon fiber composite makes that part about 2-5 times lighter than if an aluminum or steel part is used. That simple, single factor has revolutionized the design and manufacture of motorcycles (and airplanes and autos, too).

Well, before I leave off, I just want to point out that it’s not only professional racers who like to go fast and thus incorporate carbon fiber “bits” into their bikes. Motorcyclists who ride for fun, enjoy the occasional track day, and commute on our motorcycles, appreciate a strong yet light machine. Oh, and carbon fiber also looks pretty stylish and “racy” to those of us who admire the speed and the design of modern bikes. Below are two photos of stock carbon fiber parts on my Ducati Hypermotard 1100 and one of the after market exhaust on my husband’s Hyper. (So far mine is stock, but perhaps the future holds some mod’s for me, too. Oh, and I also recently fell in love with a beautiful helmet that is wrapped in carbon fiber. Drool …)

Phew! All of this “talking” is making me thirsty. Stay tuned for my next post about my favorite inorganic molecule (water) and its connection to motorcycling. It’s very cool. (OK, I heard you groan…)

Please share your comments and photos with me! I’d love to see them.

Motorcycles & Molecules – What’s the Connection?

In 1989, I began my teaching career as a Chemistry Professor at San Diego Miramar College, a two-year community college in San Diego, California, USA.  In 1990, my boyfriend (now husband), Frank, introduced me to his 1987 Ducati 750 F-1.  It was love at first sight, although I had to wait until after my dad passed away in 1994 to get on a motorcycle.  (Dad lost his cousin to a motorcycle accident at 19, and just couldn’t bear seeing his only child on a “death machine”.  I had to respect his wishes.)

In the late summer of 1994, I rode behind Frank on the back of a Harley Sportster that we rented while on vacation in San Francisco.  It was great fun, but I decided almost immediately that I needed to learn to ride.  We were planning to marry and start a family in the next 4-6 years (before I turned 40) and I wanted to learn to ride before then!

Within a year I signed up for the Motorcycle Safety Foundation riding course and the instructor told me that I was “a natural”!  I passed my written exam with 100% correct and my riding exam the next week with flying colors!  I was hooked; I was a “woman on a motorcycle”; woot!

I have loved every minute of riding, but have not had as much seat time as I would have wanted ideally; first, due to my pregnancy and the birth of our son; second, due to a herniated lumbar disc.  I have not ridden much in the last 8 years and have been living vicariously through televised or Internet viewing of every racing series that I can find time to watch, attending as many live racing  events as possible, and following numerous racing series and racers (especially female racers) on Twitter and Instagram.

One of my goals for 2017 is to develop the upper body and core strength to be able to ride my (new to me, last year) 2009 Ducati Hypermotard (currently being kept “warm” by Frank when he’s not riding his own Hyper or my Suzuki DRZ400SM).  Another goal for 2017 is to continue posting to this blog, “Motorcycles and Molecules”, that will interweave my passion for bikes and chemistry.

Stay tuned for my next post about carbon fiber and how a motorcycle enthusiast/organic chemist can appreciate it from two different perspectives.

Ride within your limits; enjoy every ride as if it was your last; and live to ride another day!


Daphne — Twitter/Instagram (@d_figuer)