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Anyone has experimented this beffore?

Today, i started my bike and when i gave some throttle twist... The sound was not continous and black Smoke and black water (looks like...) came out of my exhaust.... I never modify my exhaust ou any Fuel mods... This is a stock bike! And when the engine got hot enough then everything worked fine.... But this is weirdo because my friends bike parked Next to mine work perfectly fine, even on cold start... Is this thing normal?
 

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Sounds like another case of easy break-in. If it is black smoke, it will always do that at start-up. Just keep an eye on your oil level from here on out. Chances are, the rings never fully seated during break-in, unless your bike is still in break-in mode, which would be normal until the rings seat. It is not the end of the world, just something you will have to live with.
 

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black smoke is fuel..if it only does it on cold starts, I wouldn't worry about it even a little bit....as far as the water is concerned, its just condensation and is perfectly normal.
 
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Correct, black smoke can be fuel, but it can also be oil. Water is condensation. The best way to tell if it is oil is to have someone follow you after warm-up, jump on it hard, and rifle through the gears. If it is oil, it will puff at each shift. The rider behind you will see and smell it.
 

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I guess its possible , but I have never seen oil that caused black smoke when burned. . I also would not suspect the rings since he stated it only did it when cold...worn rings or rings that had not seated would smoke all the time and would be worse when warmed up. ....
if I were diagnosing a cold start oil smoke, I would be looking at valve guides and or valve guide seals, both of which are very very uncommon on low mileage bikes. ....in any event, I stand by my statement that nothing is really wrong with the bike....perhaps its just a bit cold blooded.
 

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I ruled out valve guides and seats because it was new. I have seen my share of black smoke from oil on terminal automobile engines. Oil can get by the rings and settle on top of pistons when sitting and combust at startup with the fuel, but I agree, either way it is not a major issue. I sold many a new BMW that had oil consumption issues due to easy break-in, and they basically told the customers to live with it, that it was normal.
 

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Is it also hard to start when hot ?

A injector not closing properly will leave excess fuel and black smoke but because of the rich mixture it will be a little slow to start when hot.

Smell your oil does it smell like fuel ?
 

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Unseated rings smoke worst when cold.... btdt.


I guess its possible , but I have never seen oil that caused black smoke when burned. . I also would not suspect the rings since he stated it only did it when cold...worn rings or rings that had not seated would smoke all the time and would be worse when warmed up. ....
if I were diagnosing a cold start oil smoke, I would be looking at valve guides and or valve guide seals, both of which are very very uncommon on low mileage bikes. ....in any event, I stand by my statement that nothing is really wrong with the bike....perhaps its just a bit cold blooded.
 
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