10' Yz450F Fuel in the oil?

I'd like to see some results too but I don't have the problem so I can't do one. I still think some people are over reacting, not all of them but the human brain does funny things when it gets an idea planted in it from the interweb :thumbsup: (always wanted to use that smiley)

DONE!

1-2 weeks till it comes..

Be sure to take the sample per the instructions. It is important that the bike be shut off after it reaches operating temperature (at least 30-40 minutes run time), and NOT COLD STARTED between then and the time the sample is taken. Since you'll more than likely have to use the drain to access the oil, be sure to clean around it thoroughly, including removing any cleaning solvent residue. The instruction sheet will have more info.

Thx, I will read it thoroughly.

I'll make sure that the drain plug is 100% clean.

I'm thinking two hours run time for a sample or maybe just one?

Even after one hour the oil reeks of gas...

DONE!

1-2 weeks till it comes..

Do you have a gas smell in yours? I didn't think you did. Thanks for testing either way, I'm curious for the results.

smells like gas and exhaust to tell you the truth.

I bet if I threw a match in the bucket she'd light.

smells like gas and exhaust to tell you the truth.

I bet if I threw a match in the bucket she'd light.

well then I guess your oil will be a good tester and maybe give us all some insight.

Throw the match in the bucket! Throw the match in the bucket! :thumbsup::lol::ride:

I did and it snuffed out :lol:

I'll have to try it after a fresh change :thumbsup:

remember, it is probably like alcohol. it might need to be 40% proof before it will light :thumbsup:

smells like gas and exhaust to tell you the truth.

I bet if I threw a match in the bucket she'd light.

what were the oil analysis results?

I changed the oil on my 11 today and it smelled like gas. I filled her up with some quality oil gonna ride it twice and dump it again and see whats up. Id like to hear any comments the original poster of this thread came up with? Or if anyone else has experienced this problem and how to fix it.

I am still waiting for lab results. My local yamaha rep. claims to have never heard of this problem. ( fishy ) My last oil change after 2hrs run time had an excess of 250 cc, for a total of 1200! Note: oil change only no filter.:smirk:

I believe user tech24 has been the one experimenting with a thermostat. I continue to believe that the very low coolant temperatures caused by the current weather causes an over rich condition as the EFI compensates for an engine it sees as not being warmed up, which leads to fuel in the oil. His early results seem to bear this out. Absent the thermostat, you could try covering one radiator.

Last winter I posted the same problem on my 2010 and through the help of grayracer I was able to take care of it. I ice ride my bike and put at least 30 hours a winter on it in temps of -10 to 40 farenheit. I now run one radiator completly taped off and the other 80-90% blocked to obtain a 180 degree water temp. There are plenty of days I have the radiators 100% blocked. I also ride the bike on dirt and you will see fuel dilution up to 50 degrees farenheit in my expierience. A thermostat would definitely be the easiset solution and I know somebody was trying to make something work on here but I am not sure what the end result was.

As grayracer said the low coolant temp sure seems to be the culprit as the EFI never sees the engine warm and keeps throwing fuel at it. I used my yamaha tuner to observe water temp, had it taped right to the handlebars and my bike would run 80-100 degree water temp while ice riding. I then kept taping up the radiators until i ran out of surface area to tape with 100% blockage. Yamaha also told me they never heard of the problem but I did inquire december of 09 about it so I am sure they were truthful to me. The rep I talked to was amazed that the bike gets ridden on a frozen lake in those temps too.

When I changed my oil in august, I noticed it had a really strong odor of gas, much more than I notice in other oil changes. I poured the removed oil into the empty liter container and there was still quite a bit more left over, I would guess at least 6 ounces. It's been awhile now, but I remember there was way too much extra oil.

I'm not sure what the issue is, but this was in the summer so it isn't just cold weather related.

.I think that the efi is rich to start, then you add more fuel if you're running the less hit map and that just makes the problem worse. Then if your like me and the track is so busy that you only get 8-10 minutes of track time per hour your bike never gets hot enough to burn off/evaporate the excess fuel. I just got my results from blackstone and I had a 10% fuel dilution in my oil which may have a little to do with the fact that I didn't have it a operational temps, only warmed it up for 10 minutes, before I changed the oil. I wonder if yoshimuras pim+data box which monitors the egr and automaticly adjusts the fuel mixture would help keep the bike from running too rich.

I just got my results from blackstone and I had a 10% fuel dilution in my oil which may have a little to do with the fact that I didn't have it a operational temps, only warmed it up for 10 minutes, before I changed the oil.
Blackstone's instructions warn you specifically NOT to do that.

I just got my canister today, and yes they say drive the vehicle for 20 minutes at least before taking a sample. Take the sample from mid draining and not the first bit of oil that runs out, nor the last but inbetween.

Pretty neat, However It's -40 degree's celcius tomorrow... There's no way in hell I'm riding in anything below -10 anymore, not with what happened last time.

Maybe next weekend I'll give it a good ride and get this sample sent out!

I'm planning on blocking the rads a bit more this time, I want to have a 70-80 C running temperature for the duration of the ride. I have a feeling that what I've heard is right, in which the engine has to be in the operating range in order to seal properly and not allow excess gas and blowby into the crankcase, polluting the oil.

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