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· Registered
9 Posts
Discussion Starter · #1 ·
Hey everyone

i need some help please

so I got a ninja 300 and on it is a MGP slip on and a power commander. When I got the bike about a year ago it was running on a yoshimura map with the MGP slip on and had black smoke coming out of the exhaust so I decided to change it to the a stock map which fixed it.

I had ridin the bike before But right now it’s being sitting for a while like couple months in the garage and I was going to take out for a ride but then noticed a leak coming from where the Slip on connects to the pipe and when I tried smelling it didn’t smell like anything but It was black im not sure what is it. Inside of the slip on was dry before turning it on and when I turned it on and leak happened it was wet no sure if this means anything.
Leak is also small but u can see something it dripping

I also checked the engine oil but it kind of smelt like gas not sure if that’s normal
If any one knows what this is and what’s going on it will be much appreciated thanks.

i also did have a problem with the engine oil where the inside of the cap was white but now that does seem to occur

The picture is the problem i had before if u zoom u can kind of the white stuff
Tire Automotive tire Wheel Light Crankset

Any help would be appreciated thanks


· Super Moderator
835 Posts
No fluid should be inside the pipe or the slip on. Is there a chance that water came into the pipe while or before it sat in the garage?

The oil shouldn't smell like gas. Gas contaminating the oil could dilute and reduce its lubricating capabilities. Not a good thing.
Is the oil level ok? How long since the last oil change? I would change the oil and keep checking its level and its odor.
Does the bike run well?
If you drain the oil, check if the oil plug has more of that white stuff. Maybe something degraded inside and is suspended in the oil. Another reason to change oil and filter.

· Registered
443 Posts
Yeah that white stuff looks a bit odd...

Sometimes a lot of water can condense inside an exhaust as it cools and just sits over time, but it shouldn't be anything more than a few drops maybe. But either way, an exhaust leak is an exhaust leak if fluid (and presumably exhaust gasses) can escape anywhere other than out the muffler. If that is the case, maybe take the slip-on off and check for gaskets, and replace if there is any in there.

Topaz is right on the money too. Maybe some engine sealant or something came off inside the engine and is circulating in the oil. Not a good thing, but not the end of the world. That's what filters are for! I would idle or ride the bike just enough to get the engine fully or mostly warmed up, and do the oil change. That way, you force any debris in the oil right into the filter, and anything that doesn't get to the filter is then in hot, more freely flowing oil, and will hopefully come out when you do an oil change. And when you do the drain, really tip the bike around, give it a shake, and open the filler cap to really let all the oil come out for a good while.

I would only really be concerned if the issues of gas smell and stuff in the oil persist past an oil change, and dusting the bike off and getting some miles on it. Things tend to get gross and clumpy when they sit too long!

Hope this helps.

· Registered
496 Posts
Was it a cool day? I suspect the fluid in the exhaust was simply condensation from hot, humid exhaust (water vapour is a byproduct of combustion) hitting cold metal. The dark colour would come from the exhaust particulates that are stuck to the inside of the exhaust.
"Leaking" from where you noticed might not be a problem, many bike mufflers aren't perfectly sealed to the pipe. Some of them literally slip over the pipe and are held in place with a couple of springs to allow the muffler and pipe to slide due to thermal expansion.

· Registered
660 Posts
In my opinion, both issues are from moisture/condensation.

If the engine isn't run enough to get up to operating temp, and stay there, the condensation inside the engine and exhaust will not evaporate.

Water boils at 100C/212F, and the oil needs to get to that point and stay there long enough to evaporate moisture and unburned fuel.

Carbed 250s would drain gas from the tank into the oil if the petcock and float valves malfunctioned, but it would be odd for a 300, because it is F.I., to dump fuel into the oil. I think it's just typical unburned fuel from the rich condition at start-up that hasn't burned off.

My suggestion would be to go for a long ride. That will evaporate all the water and fuel in the oil and moisture in the exhaust system.

That's one of the reasons that starting an engine during storage to "warm it up" is a bad idea. Even extended idling isn't going to get the engine hot enough to burn off the contaminants and moisture that you are putting into the engine during start-up. It takes a decent amount of actual riding to do it.
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