Joe Rocket Sahara Vest product review:
Cooling Vest

What is an evaporative cooling vest and why wear one during hot weather motorcycle riding?

Good questions.

Intro

Anyone who rides a motorcycle in the hot summer months knows how challenging it can be to remain reasonably comfortable and to protect against overheating and dehydration.

In these conditions, an evaporative cooling vest can be a strong ally in your fight against overheating.

How does it work?

The Joe Rocket Sahara cooling vest functions on the principle of evaporative cooling. That is, when a liquid evaporates from a surface, it takes heat along with it, cooling that surface.

When wearing the Joe Rocket Sahara vest, the vest will feel cool to the touch, even when standing around in the hot sun. But the higher the airflow, the greater the rate of evaporation and therefore the amount of body cooling.

Note: the following factors affect the rate of evaporation and therefore the effectiveness of the cooling vest: air temperature, the amount of humidity in the air, and the amount of airflow available.

The hotter the temperature, the drier the air, the higher the rate of evaporation and the higher the body cooling effect.

If relative humidity levels are high, you will need higher amounts of airflow for an evaporative cooling effect.

How to activate it:

If activating the Sahara vest from a completely dry state, just soak it in water for between 2 to 5 minutes. This could be in a bucket, a pail, a sink, or even a plastic bag (ie when on the road). It will quickly begin absorbing the water, a little like a blotter does.

The longer you soak it, the more water it absorbs and the longer it will cool. For a short ride, 2 or 3 minutes may be enough. For longer rides and hotter temperatures, you may wish to soak it for 5-8 minutes. The absorbent material within the cooling vest soaks up and swells with the water.

Of course water adds weight. But when riding a motorcycle in hot temperatures, you will not notice this extra weight. What you will notice is the extended period of time that you will enjoy the body cooling.

The temperature of the water used in soaking does not matter much. Whether it is icy cold or lukewarm. As soon as evaporation begins, the vest will become cool to the touch.

To recharge the cooling vest from partially dry (ie while riding) just bunch it up and pass it under a tap of running water for 60 to 90 seconds. You’ll then be good for another couple of hours of evaporative body cooling.

Description: Sahara Cooling Vest

Features

As opposed to the outside of the cooling vest, where the material quickly absorbs water (almost like a blotter) the inner liner is mostly non-absorbent.

Laying the vest flat on a table and pouring a couple of tablespoons of water over the inside liner has the water beading up. It then is slowly absorbed over a period of approximately 10 minutes.

This helps explain why my t-shirt does not get wet when wearing the Sahara vest.

In fact, I don’t even find it necessary to wipe the inside liner dry after recharging the cooling vest with water.

Note: Some evaporative cooling vests will soak your clothes with water. The cooling principle remains the same though these vests may tend to make you feel somewhat clammy after a while.

Limitations:

Though the Joe Rocket Sahara vest will be less effective in very humid climates, it can be used as a passive heat sink by simply pre-chilling it.

Just activate the vest by soaking it in water. Place it in a plastic bag and let it sit in a refrigerator for a spell.

You will then have a cooling vest that will act as a passive heat sink, absorbing your body heat and cooling you by conduction.

Though the body cooling effect will not last nearly as long as when the vest cools by evaporation, it is nevertheless a useful tactic when dealing with days where humidity levels are very high.

Note: You might want to resist the temptation of over chilling your vest. There is evidence that wearing something too cold next to the skin results in paradoxical body cooling. That is, your surface blood vessels initially constrict due to the shock cooling effect.

This temporarily decreases heat transfer from your body core to your periphery. When this occurs, you may feel cool on the outside, but your core body temperature will initially increase.

Additional benefits

An additional benefit of wearing an evaporative cooling vest is that you will sweat less. This can make a significant difference as it allows your body to expend less energy in trying to cool itself off. So you can ride for longer periods with less physical stress and fatigue.

Though it is designed to integrate by zipping in with current Joe Rocket mesh jackets, the Sahara vest can be worn under any mesh or adequately perforated leather jacket.

Note: if you wear the Sahara vest as a cool weather liner (ie windbreaker) make sure that it is absolutely (100%) dry. This is critical, as any dampness within the vest will result in evaporative cooling of the vest and therefore have some body cooling effect on you.

My impressions

The body cooling effect is noticeable.

Like a heated vest that concentrates heat on your body core, the cooling vest concentrates cooling on your body core. And, like a heated vest, a snug fit ensures a higher transfer. To allow this, the Sahara is constructed with 2 wide elastics going down the sides.

In keeping with the importance of having a snug fit, it may be better, especially when riding in very hot weather, to wear the Sahara vest unzipped from the jacket but zipped up like a regular vest. This will keep the vest in contact with your chest and back rather than being in contact with the jacket.

Though you are aware that you are wearing something cool and damp when wearing the Sahara vest, you don’t feel wet and your clothes don’t get soaked.

Additional benefit: You can wear the Joe Rocket Sahara vest while doing chores around the yard, working in a hot garage, or even in the house during heat spells if your A/C is down. The benefits of a cooling vest are not limited to motorcycle riding.

Wearing the Sahara vest in very hot weather makes the difference between unbearable heat and heat that is comfortably bearable. It can even improve comfort while sitting in traffic. This is significant.