Spewing (moisture out of the exhaust)

[Nevets]

I couldn’t handle being inside anymore today, so I got the bike out for a ride. Pretty darn cold for me at about 25F, since I have been too cheap to buy a heated vest yet. But hey, at least the sun was out for a change! As I was preparing to leave, I noticed a fair amount of steam coming out of the exhaust pipe. Nothing unusual, since living in Michigan, steam out of the exhaust on a cold day is a very common scene. I noticed moisture that had been spewed out on to the cement floor.

 

When I arrived home, and considered that the bike would most likely be not ridden full time for another month, I started thinking….

 

Presumably moisture in the exhaust is present due to condensation. Right?

 

Where exactly is the moisture/steam coming out of? Obviously the exhaust, but where exactly? Is the moisture setting in one area that would cause the pipes to rot out? They are stainless, right?

 

Should any precautions be taken to minimize the collection of moisture in the exhaust? Cover the end with aluminum foil or something similar?

 

Your thoughts on the subject would be appreciated. While any suggestions of moving to a warmer climate are appreciated, they are unlikely to be realized.

[BakersRT]

CO2 & Water are a few of the by-products of combustion. The key in my opinion is to get the exhaust system hot enough that any water present will boil off.

[BchrisL]

Gasoline is basically made up of a molecule called Octane. It has 8 carbon atoms and 18 hydrogen atoms (a hydrocarbon): C8H18. When it combines with oxygen, you get 8 new molecules of carbon dioxide (co2) and 9 molecules of water vapor (h2o), and also a lot of energy is released in the form of heat. The water starts out as gas (steam), but as the temperature cools it condenses into water droplets.

 

The water is being produced by the gasoline the engine is burning.

 

Chris

[Nevets]

Well then, looks like I had no idea what was really going on. I had the false impression the moisture was entering the pipes from outside.

 

So, as long as one runs it up hot enough to dissipate any condensed moisture from initial operation, no worries! Makes sense.

 

Boy, it never ceases to amaze me how little I know…..

 

Thanks for clearing that up. Now if I can figure out why it stalls once in a while….

[DogGone]

Steve, you'll see the same thing with cars. Take a look next time you're out on the road. Usually early morn at stoplights.

 

I know people who hate to drive/ride short distances because they worry about moisture collecting in the exhaust and rusting it out.

 

Another weird phenomena that i haven't noticed with the bmw is engine oil getting frothy/milky when the bike is ridden a short distance and doesn't warm up. My Cagiva does this. Once again, moisture is the culprit. Looks scary, but not a problem.

 

pete