So Yamaha still has no clue about gas in the oil?

Ive done a search on here and read through all the threads about the smell of gas in your oil. Some people saying to block off the radiators,other say the cold temps are causing it, bad gas,rich maps ect...?? Ive done two oil changes on my 2011 and both times its like gas is pouring out of my drain holes.:thumbsup: I called my dealer today he said I was only the second one to bring this up. I have tons of friends that have 2010/11 yz 450's and only one of them said "yes my oil smells like gas so i change my oil more often'

Sorry but I spend 8k on a bike and its got a problem it should be fixed my yamaha not these band aid fixes I find on thumper talk. I run very good quality oil so I can get away with riding the track 3-5 times before changing it. Now I have to start doing it every ride or two because my oil is completely contaminated with gas?? I dont know but imo this is a problem. I had a 2010 yz 450 and it did not have this problem ran the same oil and gas I been running in the 11'

So what now? Stop running Motorex oil change over to penzoil and change my oil after every 6-10 laps at the track so mentally I know my motor is being lubricated with oil not gas.. Or does Yamaha step up and and have a recall that fixes the problem.

Ive done a search on here and read through all the threads about the smell of gas in your oil. Some people saying to block off the radiators,other say the cold temps are causing it, bad gas,rich maps ect...?? Ive done two oil changes on my 2011 and both times its like gas is pouring out of my drain holes.:thumbsup: I called my dealer today he said I was only the second one to bring this up. I have tons of friends that have 2010/11 yz 450's and only one of them said "yes my oil smells like gas so i change my oil more often'

Sorry but I spend 8k on a bike and its got a problem it should be fixed my yamaha not these band aid fixes I find on thumper talk. I run very good quality oil so I can get away with riding the track 3-5 times before changing it. Now I have to start doing it every ride or two because my oil is completely contaminated with gas?? I dont know but imo this is a problem. I had a 2010 yz 450 and it did not have this problem ran the same oil and gas I been running in the 11'

So what now? Stop running Motorex oil change over to penzoil and change my oil after every 6-10 laps at the track so mentally I know my motor is being lubricated with oil not gas.. Or does Yamaha step up and and have a recall that fixes the problem.

have not heard of that problem with the Yz...only the CRF...which Honda does acknowlege....They say it wont hurt anything...just change oil more often. Sounds kinda hokie to me.

I confirmed with eddie in the fuel injection forum and he said the difference between the honda and the yammy is a leaky injector. The Honda has fuel in the gas, literally, where you pull the fill plug and gas pours out, this is a leaky injector issue and needs to be resolved for obvious reasons.

Gas smell in the oil is what he called normal for FI bikes.

The problem seems to be because the bike is not reaching operating temp and is being overcooled. This is somewhat true if you ride in temps below 20 celcius, the rads cool the bike quite a bit.

Last sunday I was riding all day in +10 degree weather with the complete left rad blocked off with cardboard. Bike never went over 90 degree's (even in really really tight stuff) and stayed at about 60 degree's the whole day (still too cold, you want 70-80 degree's for coolant temps).

The bike needs a thermostat, if you can get one in there, you'll most likely find that the gas smell in the oil will be completely gone. Otherwise your going to have to deal with it, cause it won't go away unless you can keep the engine temp at a consistant 70 degree's celcius or higher.

I still have a blackstone labs container for oil analysis and I'm just about ready to send in my oil with the rad blocked off and the bike running at higher temps. Until someone does this we don't really know if the smell of gas in the oil is just a smell, or if it's deteriorating the oil cause there is literally small amounts of gas in the oil...

Thanks for the replies. Brentn ya I read your post from a thread a year or so ago about it. The bike has been ridden in 75* weather or higher and im no factory rider or even a pro but I can ride id be real surprised my bike was not getting hot enough. As I said, I had a 2010 yz 450 and this never happened. The oil I use even after 6-9 hours of riding would look pretty good still and smell like oil still.

On the 2011 since the first oil change the oil pours out like water not as thin but just not the same as my 2010 where it still was thick like oil. And what Eddy said could be the case but in 2010 I owned and rode 2010 rmz 450, crf 450,kx 450,ktm 450 and yamaha 450. None of them had this oil in the gas issue not one of them and they are all FI besides the 10 ktm.

I think the reason this has got to me so much is that I bought all the bikes in 2010 and even an 11 ktm 450 to ride them and see what I really liked for my height ,size,speed and what I felt would be best for me. I have my personal opinions on all the bikes but I chose the Yamaha MOSTLY because there usually bulletproof. I was able to get all the bike pretty comfy but I still liked the Yamaha a lot so thats what ill be riding for now on. So now im stuck with a bike that im losing confidence in. I mean gas in your oil in there just cant be good for the bike. It has to be degrading the chemical in the oil that is in there to protect. Changing the oil more often is not an answer imo. Or blocking the rad's.. If it needs a thermostat then Yamaha should stick one on there.

I just put fresh oil and filter in yesterday going to ride today and dump the oil and see what it smells and looks like. If im not happy ill clean the bike up and bring it back to the dealership tomorrow.

I still have a blackstone labs container for oil analysis and I'm just about ready to send in my oil with the rad blocked off and the bike running at higher temps. Until someone does this we don't really know if the smell of gas in the oil is just a smell, or if it's deteriorating the oil cause there is literally small amounts of gas in the oil...

Just for reference, if you have a carbureted YZ450, and you run a totally normal cold start on the engine, then shut it down before the engine has run up to temp for 15 minutes, the oil analysis will show "significant" fuel.

But you can send a note with your sample asking the lab to comment on the quantity found as compared to cold start contamination, and what if any effect it may have on oil performance.

I might have to prepare a new sample then, I don't want to obscure the results. I have been cold starting the bike often and shutting it down rather quick.

Going to need to change this oil, and keep the bike on a 4 hour course of only starting it when I'm riding it. Due time fellas :thumbsup:

Thanks for the replies. Brentn ya I read your post from a thread a year or so ago about it. The bike has been ridden in 75* weather or higher and im no factory rider or even a pro but I can ride id be real surprised my bike was not getting hot enough. As I said, I had a 2010 yz 450 and this never happened. The oil I use even after 6-9 hours of riding would look pretty good still and smell like oil still.

On the 2011 since the first oil change the oil pours out like water not as thin but just not the same as my 2010 where it still was thick like oil. And what Eddy said could be the case but in 2010 I owned and rode 2010 rmz 450, crf 450,kx 450,ktm 450 and yamaha 450. None of them had this oil in the gas issue not one of them and they are all FI besides the 10 ktm.

I think the reason this has got to me so much is that I bought all the bikes in 2010 and even an 11 ktm 450 to ride them and see what I really liked for my height ,size,speed and what I felt would be best for me. I have my personal opinions on all the bikes but I chose the Yamaha MOSTLY because there usually bulletproof. I was able to get all the bike pretty comfy but I still liked the Yamaha a lot so thats what ill be riding for now on. So now im stuck with a bike that im losing confidence in. I mean gas in your oil in there just cant be good for the bike. It has to be degrading the chemical in the oil that is in there to protect. Changing the oil more often is not an answer imo. Or blocking the rad's.. If it needs a thermostat then Yamaha should stick one on there.

I just put fresh oil and filter in yesterday going to ride today and dump the oil and see what it smells and looks like. If im not happy ill clean the bike up and bring it back to the dealership tomorrow.

You make some really good points that I just can't contradict, I might have to re-think what I think is causing this...

Truth be told though when the oil-analysis is complete.

Like I mentioned before, for the test I want to keep engine temps up (blocking one rad), starting only to ride the bike and not just to warm up and then shut off (garage stuff). If you guys have any other controls you think I should have, let me know.

You could be right, and Hoss could be right, too. It could well be that the fuel smell in the oil is the result of rich mixtures for all the reasons you state, and yet Hoss might have a leaky injector.

Hoss, try removing the injector without disconnecting it, or unbolting the throttle body from the head and let it hang free, then kick it a number of times to raise fuel pressure and watch what it does. It should only drip a couple of times or less after you stop kicking.

Injector is real easy to get at with these bikes, I was thinking of possible hooking up a 12V battery to the fuel pump lead. There is no fuel pressure regulator that I can see, nor a return fuel line to support such a system. Point being I don't think you could over-load the fuel line/pump or injector of pressure by doing it this way, and it might be a better way to see how well the injector holds up?

Then again I don't want to risk a costly fuel pump replacement... :thumbsup:

My bud has this problem on a Honda. Mechanic told him that fuel injectors build up pressure when motor is turned off and a little gas leaks out into engine from this pressure build up. Not sure but check into this.

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