I got a 94 CBR 900 with 18K miles, everything runs find, powerful. But I notice some foggy white smoke exhausting when choked idle? Once warmmed up, it's ok? Do anyone have similar problem? Please advise bestway to maintain? Is this a sign of something much worst coming?? hope not.

 

You should be fine, unless it's a ridiculous amount. Blue smoke, black smoke, not so great.

White when cold=normal

 

It's hard to say without seeing the smoke or how much of it there is. White smoke is usually coolant. If it smells at all sweet you could have a head gasket going bad. When it wams up the metal is expanding and compressing the gasket. I wouldn't worry too much, just keep an eye on it for now and watch for it to get worse. Also, check your coolant level regularly and see if it seems to go down.

 

Keep a check of your engine oil level. Depreciation of it will be a not so good sign.

 

Dinez you're online, cool. I figured white couldn't be oil. Was I wrong?

 

Blue smoke is oil
Black smoke is bad A/F ratio-running rich
White Smoke is Coolant

If you have white smoke it is important to determine if you have a head gasket issue. Your block and head are aluminum, and aluminum oxidizes when it comes in contact with water. So, a failing head gasket will seriously compromise you head and block sealing surfaces. If ignored, the problem will get worse, and you may warp your head or if it gets really out of hand you could vapor lock your engine...not cool! Your coolant level should be dropping if you have a head leak, and there may be oil residue mixed in with it if you leak is near an oil passage. The "sweet" smell as mentioned above is also a dead giveaway. If you find you have a failing head gasket then you must bite the bullet and replace it immediately, or run the risk of replacing the whole engine. I hate to be Mr. Bad News all the time, but, you can fix this issue before it does major harm. It sucks I know but it will be worth it. Now, before you go nuts I also want to mention that if you store your bike in a warm humid area and then take it into the cooler outside air, you might be causing that air to condense and the cylinders might be getting a little moist. Or if your garage is cool, and you take the bike into real hot outdoor weather the same will happen. This will only be noticeable for a minute or two, and really it doesn't result in white smoke, its just a little side note. Good luck with the whole deal, just handle it now in the off season before spring rolls around again.

 

Fighter, the coolant level will drop because of a head leak and does it necessary to be a oil slippage too?

This whole smoke things from the bike could be totally nothing too as mentioned by fighter because it can be caused by cold or long period storage.

 

What's up Dinez? I had a SUpra not too long ago with a blown HG and its really luck of the draw when it comes to seeing oil mixed with coolant. It depends on where the leak has occurred. At the time I actually used a 4 gas analyzer off of an emissions machine at my job to "sniff" the antifreeze in my radiator and the analyzer could pick up the hydrocarbons in the coolant. That is not a totally foolproof approach but if you see coolant level dropping then thats your best diagnostic tool. I had an idea for my supra at the time: I was going to make an air fitting that would thread into the spark plug hole and then I wanted to put some low pressure compressed air into each cylinder and see if I could see any air bubbles in my radiator or coolant. I know that most of the pressure would escape throught the ring gap but I was just tinkering with the idea of how to pressurize each cylinder and try to narrow down the leak. Of course the spark plugs of the offending cylinder might look a little more wet than the others, and that is a dead givaway. Estate, check the plugs and see if any one looks different than the others. Have a great THankgiving guys.

 

Thanks fighter for the info. Just wondering if the oil going to slip when the coolant is leaking, what color the smoke going to be?

 

White and blue would be my guess, but thats really hard to tell from just looking at it. I would think that if they are being mixed you would see some water in the oil. I know my Supra had oil in the coolant and water in the oil pan when I drained the oil. And that thing would just puff white smoke until it warmed up. I could also hear air in the coolant system running through the dash, it gurgled and made all kinds of funny sounds. Bikes are harder and easier to diagnose. I just know from my experience with HG that I would always want to be safe and not sorry.