Author Topic: cleaned carbs on, a little smokey?  (Read 6187 times)

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Offline cudjo

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cleaned carbs on, a little smokey?
« on: May 10, 2009, 11:31:14 AM »
Just cleaned my carbs ;D
put them back on and the bike stated right up ;D ;D.....that was the first time it did that!

she idles at around 1k and 2 k with the choke up. (choke does not want to stay up. but i remember glossing over a fix for that in the manual, so I will get to that)

after a min. or two of idle the exhaust gets a little smokey, and it seemed like there was smoke coming out of where the  the #2 pipe connects to the engine.
the bike was in a damp area while the carbs were off, and it was raining like crazy. there should not have been any direct rain on the bike. could it be that enough moisture got into the engine while the carbs were off, and that be causing the smoke?
if so do I just let it burn off?
the bike still has to be synced and all that, so if someone knows if I should look for things to straighten out once its sunk?

Offline TwoTired

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Re: cleaned carbs on, a little smokey?
« Reply #1 on: May 10, 2009, 11:38:17 AM »
Blue smoke = oil
black smoke = soot,unburned fuel
White smoke = Water vapor, steam/ (on an air cooled bike it is usually condensation within the muffler.)  If condensation, it will likely convert to steam and exit after the pipe reaches a normal temperature over time, say 20 minutes on the freeway.

Check your head pipe temps.  Are the about the same for each one?
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Offline 1timduke

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Re: cleaned carbs on, a little smokey?
« Reply #2 on: May 10, 2009, 12:16:30 PM »
If the smoke is coming from the joint itself where the pipe meets then you need to get some new exhaust gaskets.   Leaky gaskets cause an upset in exhaust pressure, causing poor running.   They're really cheap and easy to put on.

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Offline cudjo

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Re: cleaned carbs on, a little smokey?
« Reply #3 on: May 10, 2009, 01:01:41 PM »
Blue smoke = oil
black smoke = soot,unburned fuel
White smoke = Water vapor, steam/ (on an air cooled bike it is usually condensation within the muffler.)  If condensation, it will likely convert to steam and exit after the pipe reaches a normal temperature over time, say 20 minutes on the freeway.

Check your head pipe temps.  Are the about the same for each one?

I would deff. call it white smoke.

thanks TT, your the man!

dont have a thermometer, for the pipes, but i will get one and check it out. ( what exactly type of therm. do I need for that?)

Offline scunny

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Re: cleaned carbs on, a little smokey?
« Reply #4 on: May 10, 2009, 02:15:07 PM »
poor mans thermometer. spit on finger and touch header lightly
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Offline Bob Wessner

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Re: cleaned carbs on, a little smokey?
« Reply #5 on: May 10, 2009, 02:33:18 PM »
dont have a thermometer, for the pipes, but i will get one and check it out. ( what exactly type of therm. do I need for that?)

If you have a Harbor Freight near, they sell small, inexpensive infra-red therms. that are quite accurate and can be handy around the house as well.
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Offline heffay

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Re: cleaned carbs on, a little smokey?
« Reply #6 on: May 10, 2009, 02:52:16 PM »
poor mans thermometer. spit on finger and touch header lightly

stupid man's thermometer... just wrap a hand around each one.   ;D
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Offline Duke McDukiedook

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Re: cleaned carbs on, a little smokey?
« Reply #7 on: May 10, 2009, 03:00:10 PM »
Just got done cleaning my carbs also. # 2 heated up like it should finally to match the other three and a little smoking occured where there was unburned stuff (oil, etc.)

The same occurred once I changed out my new, bad coil for 2-3 from partsnmore with some Dyna coils. The smoking stopped once it bruned off all the crap in the header.
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Offline cudjo

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Re: cleaned carbs on, a little smokey?
« Reply #8 on: May 10, 2009, 03:18:25 PM »
ya I spit  on all of em b4 , they are all sizzlin...tsssssss.... and seem to have the same sizzle  level. not sure if the viscosity of my spit was the same  though. might have to do that one again ;)

Offline mystic_1

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Re: cleaned carbs on, a little smokey?
« Reply #9 on: May 10, 2009, 03:45:10 PM »
poor mans thermometer. spit on finger and touch header lightly

stupid man's thermometer... just wrap a hand around each one.   ;D

Id10t thermometer, bump forehead on pipes while checking tire pressure.   :o   ::) :'(

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Offline cudjo

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Re: cleaned carbs on, a little smokey?
« Reply #10 on: May 12, 2009, 09:59:13 AM »
took off the pipes to derustify, there was no water in them?

I figured that there would be a fair amount in there to cause the smoke, but there was none.
should I be able to see the water, should i be able to pour it out if the pipes are off?

also now that the pipes are off what do the gaskets look like that are supposed to be between the pipes and the engine?

is there anything I should check for while the pipes are off?

Offline heffay

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Re: cleaned carbs on, a little smokey?
« Reply #11 on: May 12, 2009, 10:00:39 AM »
exhaust gaskets are a crush type... can be cloth wrapped w/ wire or crush copper gaskets.
they are typically toast after one or two installations.
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Offline cudjo

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Re: cleaned carbs on, a little smokey?
« Reply #12 on: May 12, 2009, 10:20:15 AM »
so they are the metal slides on the end of the pipes?

Offline heffay

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Re: cleaned carbs on, a little smokey?
« Reply #13 on: May 12, 2009, 10:30:10 AM »
i think what you are talking about are the exhaust flanges... the parts that hold the headers on, correct?  they are finned?  those are not the gaskets, you may not even be able to see the gaskets since they are covered in carbon/soot.  they'll be stuck to the exhaust ports on the motor most likely.
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Offline cudjo

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Re: cleaned carbs on, a little smokey?
« Reply #14 on: May 12, 2009, 10:33:52 AM »
ya, I just found a pict online of wht the gasket looks like.
I will get in there and see what they are looking like.

thx

Offline TwoTired

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Re: cleaned carbs on, a little smokey?
« Reply #15 on: May 12, 2009, 10:40:58 AM »
took off the pipes to derustify, there was no water in them?

I figured that there would be a fair amount in there to cause the smoke, but there was none.
should I be able to see the water, should i be able to pour it out if the pipes are off?

also now that the pipes are off what do the gaskets look like that are supposed to be between the pipes and the engine?

is there anything I should check for while the pipes are off?

Ever see water form on the outside of an iced beverage?  This is condensation that collects from the humidity in the warmer air making contact with the cold glass surface.  Saturated air can no longer hold suspended moisture, and this is deposited on the wall of the glass.

Whenever the air inside the muffler is warmer than the outside air, this same condition exists.  Humidity in the air gets deposited on the inner wall of the muffler/ pipe as condensation. The water is a byproduct of combustion and it can also come from the outside air. It can build over time if the engine never gets the pipe to a temperature to evaporate all the water collected throughout the pipe.  There is usually a hole in the pipe system at the low point to drain off large excesses, but the condensation can easily stick to the pipe walls just as it does on the outside of that drinking glass.

When the pipe heats, it slowly turns the water into vapor.  Just as when you boil water on the stove, it doesn't turn all the water to steam at once, it does it gradually until it is all gone.  That is why I told you to run the bike on the freeway for 20 minutes or so, in order for the engine heat to warm the pipe to a temperature that eventually turns all the condensation to water vapor an pushes it out the end of the pipe.

The cycle is repetitive, by the way.  As the pipe cools down, more condensation builds up on the inner pipe wall.  Next time you start it up and the pipe begins heating, you'll see white smoke again.  The severity of the condensation, and duration of the vapor exit, interacts with the temperature and humidity of the atmosphere where the bike lives.

The header gaskets look like copper doughnuts when new, and deform or flatten during installation.  They stick in the head and often have black deposits on them to camouflage their lurking remains.

Cheers,





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Offline cudjo

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Re: cleaned carbs on, a little smokey?
« Reply #16 on: May 12, 2009, 11:28:43 AM »
I dont see anything that resembles a gasket inside the (hole where the pipe goes...) just soot.
is it possible that there was no gasket there?

Offline TwoTired

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Re: cleaned carbs on, a little smokey?
« Reply #17 on: May 12, 2009, 01:45:45 PM »
Was it leaking?  If not, there is a gasket in there.  Use a small wire brush to clean off the soot.  I think the stock gaskets are copper.  Should see color.
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Offline mystic_1

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Re: cleaned carbs on, a little smokey?
« Reply #18 on: May 12, 2009, 02:14:11 PM »
Yes stock gaskets are copper colored and will be smashed flat to maybe 1/8 inch thickness.  It's easy to not see them under all the soot and oxidation.  The exhaust port itself is aluminum so if you scratch the soot off and see silver, no gaskets and PO was a dumbass.  If you see copper the old gaskets are there and you should pry them out with a big #3 flat head screwdriver or something.

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Offline cudjo

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Re: cleaned carbs on, a little smokey?
« Reply #19 on: May 12, 2009, 02:39:49 PM »

That is why I told you to run the bike on the freeway for 20 minutes or so, in order for the engine heat to warm the pipe to a temperature that eventually turns all the condensation to water vapor an pushes it out the end of the pipe.

the bike is not road ready yet, and when it becomes so, I will probly not be getting to the highway till I learn how to ride.

is there another way to get the water off the pipes

thx

Offline TwoTired

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Re: cleaned carbs on, a little smokey?
« Reply #20 on: May 12, 2009, 02:52:13 PM »
is there another way to get the water off the pipes

- You can pump dessicated air through them.

- Take them to the desert and let them bake in the hot sun for awhile.

- Bake them in an oven.

Why is this so important to you?
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Offline cudjo

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Re: cleaned carbs on, a little smokey?
« Reply #21 on: May 12, 2009, 03:05:17 PM »
is there another way to get the water off the pipes

- You can pump dessicated air through them.

- Take them to the desert and let them bake in the hot sun for awhile.

- Bake them in an oven.

Why is this so important to you?

just because its a lot of smoke....I dont know if I will have a hard time getting an inspection if its smoking like that ....and I want to know as much as I can, about everything :)...

Offline TwoTired

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Re: cleaned carbs on, a little smokey?
« Reply #22 on: May 12, 2009, 03:18:31 PM »
Does the smoke have a smell?  Is there a coating on the inside of the pipes?  Describe it.
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Offline J.Webster Designs

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Re: cleaned carbs on, a little smokey?
« Reply #23 on: May 12, 2009, 03:37:17 PM »
does the smoke last a while? does it only come out at certain RPM's? have you tuned the carbs yet? from your avatar, it looks like you have an F2. if that's the case you may have leaky valve guides like i think i do. but mine isn't just puffing out smoke like what i am gathering from your description.
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Offline cudjo

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Re: cleaned carbs on, a little smokey?
« Reply #24 on: May 12, 2009, 03:37:57 PM »
Does the smoke have a smell?  Is there a coating on the inside of the pipes?  Describe it.

It just smells like exhaust.... might b a little strong but its smells like exhaust to me.
inside is very sooty, and it does feel moist... Like the inside of a smoking pipe might be, kind of resiny...I guess thats where the moisture whent huh?