Help: Leak On Exhaust Pipe Drain

[CLYDE]

I understand that the small hole in the bottom of our stock exhaust canister serves as drain in case water enters the exhaust during bike wash. What i'm puzzled about is the small amount of water dripping in this hole every morning when i start the bike. This happens even if you didn't wash the bike for almost a month, the water will drip and disappears instantly as the bike warms up or when in use, but once you park the bike again and let the engine cool for an hour the small amount water drips again when u press the start button. The coolant in the radiator and reservoir doesn't change so i'm wondering where this liquid is coming from, sometimes brownish in color and a little bit oily. This is happening for almost a year and i didn't find anything abnormal with the engine sound and bike performs well. My only concern is that the stock exhaust corrodes easily and rust can be seen on the bottom of the canister. I hope someone can enlighten me regarding this problem.

 

[jcm1130]

does that happen only in stock pipe? or aftermarket pipe? maybe this is the result of ethanol on gasoline that it attracts moisture and humid on carbs thus when accumulated. it will come out of the exhaust. IMO..

 

[lpsnipie_67]

 

[CLYDE]

does that happen only in stock pipe? or aftermarket pipe? maybe this is the result of ethanol on gasoline that it attracts moisture and humid on carbs thus when accumulated. it will come out of the exhaust. IMO..

I only used XCS gasoline, it's not dripping when using aftermarket pipe because there is no drain hole at the bottom of the canister but you can notice the brownish liquid trying to come out on the rivets.

 

[CLYDE]

I condemned the AIS to remove the irritating backfire during decelaration, maybe this is the side effect of removing it.

 

[CLYDE]

I finally found the answer on Yahoo, Tnx for your replies. Here is the explanation:
Exhaust pipe condensation

Today's exhaust systems with catalytic converters get very hot when the engine is on during normal operation. Outside air which includes varying amounts of humidity is attracted to the inside of the exhaust system as it cools down.

The reason the air is attracted so well is as the engine runs the exhaust system is a hot high pressure area when the motor is on. As soon as the switch is turned off atmospheric air including the humidity of the day or night zooms right inside the entire system. When the motor switch is turned on after a cool-down period the moisture ladened air is spued out the tail pipes.

By the nature of the shape and design of the system the ceramic honeycomb inside converter and the pipe to the exhaust manifold doesn't allow condensed water to travel uphill. Thus no harm to the engine. Exhaust systems last longer than ever because of the heat generated during operation and better materials of construction

 

[hcsnipee]

i also experience this on my Snipee and i notice a small corrosion starting on that hole area.

 

[jangbest]

That water dripping came from your pipe when its colds the moist exist when metal colds. waaahhhh.... bad english ....
I also experience it on my classic sniper