Author Topic: White smoke upon cold start  (Read 971 times)

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Offline zipper

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White smoke upon cold start
« on: September 27, 2013, 06:43:33 AM »
Hi!

Just a random thought going thru my head:

Shortly after starting my CB500 K1 when cold a white smoke usually comes out the exhaust for a few minutes (at idle), and disappears after around a mile of riding.

Is that normal, or is it sign of something wearing out?

« Last Edit: September 27, 2013, 06:45:21 AM by zipper »

Offline reddyvv

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Re: White smoke upon cold start
« Reply #1 on: September 27, 2013, 07:15:57 AM »
Sounds like it's just the condensation in the pipes evaporating. How cold is the weather?

Offline evanphi

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Re: White smoke upon cold start
« Reply #2 on: September 27, 2013, 07:25:12 AM »
I've been getting it too, lately with cold starting mornings around 10 deg C or below. Just condensation!
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Offline flybox1

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Re: White smoke upon cold start
« Reply #3 on: September 27, 2013, 01:27:33 PM »
no worries...it will go away when your bike is up to operating temps. 
a good habit is allow your bike to run, or ride it until this water vapor is gone, which means any condensate is out of the exhaust system and its dry in there.   
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Offline BobbyR

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Re: White smoke upon cold start
« Reply #4 on: September 27, 2013, 02:36:23 PM »
no worries...it will go away when your bike is up to operating temps. 
a good habit is allow your bike to run, or ride it until this water vapor is gone, which means any condensate is out of the exhaust system and its dry in there.
Then moisture will condense as the pipes cool and the whole thing will happen again until summer.
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Offline zipper

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Re: White smoke upon cold start
« Reply #5 on: September 28, 2013, 02:29:47 AM »
Thanks everybody, it must be that. One thing less to worry about  :D

ps: temperature is between 7 and 15 deg C (41-60 deg F)

Offline chewbacca5000

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Re: White smoke upon cold start
« Reply #6 on: September 28, 2013, 08:54:48 AM »
I had some turnout slipons on a CB650 and had the same exact question. Upon startup on cold days it wold billow clouds of white smoke.  That particular exhaust seems to make lots of condensation.  Nothing to worry about.

Offline Mo

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Re: White smoke upon cold start
« Reply #7 on: September 29, 2013, 08:46:51 AM »
Normal!! I just turn on my bike and admire how cool the "smoke" coming off the pipes look.