Oil smells like gas
 

I've had my bike (03 954) for almost two months now. I changed the oil when I first purchased it and used Mobile 1 full synthetic motorcycle race oil. When I changed the oil I pored in the recommended 3.9 quarts, cleaned up all my stuff, started the bike to make sure everything was fine and noticed that I had put too much oil in the bike. I didn't think it would be a big deal so i didn't drain any. Now, since I've been riding the bike it seems like each week the bike gets hot faster and faster. It is to the point where it will reach 200+ degrees in a matter of minutes after start up. If I'm rolling down the highway with tons of air flow the temp sits at like 180 but if I get behind any cars or even another motorcycle the temp will start to rise. Coming to a stop light is just crazy to watch the numbers tick by. Now, the thing is that the bike never over heats. The thermostat opens up like it is supposed to, the fan comes on and life goes on. However, like I said earlier...this whole process has been happening faster and faster every week. So, last night I was checking out my coolant and it looked pretty good. To be safe I took the radiator cap off and ran the bike to make sure it had no air bubbles in it. I also had noticed that the overflow bottle had about an inch of coolant over the top fill line (because I added water when I first go the bike because I thought the coolant was low) so I drained some of the coolant from the radiator as the bike was heating up (basically I soaked up coolant each time it seemed like it was going to overflow from the radiator). After the bike ran for a bit and I turned it off I started to look at the oil window and noticed some small bubbles...it was not frothy but there were some bubbles. I undid the oil fill plug and smelled the oil on it and it smelled of gas. Today when I changed my oil I could smell the tinge of gasoline as well. I used the same brand oil again, only I made certain I filled up the engine to exactly the middle of the low fill line and the high fill line. I ran the bike for a while and it seemed better but I am yet to ride it and get a true look. Not sure when that will happen though because I have a blown fork seal and I don't mean one that just weeps a little but fully blown with a puddle of fluid on the floor.

So, the big question before I get to ride is... can someone tell me how I could have gotten gas into my oil?

If gas really is in the oil would that account for the accelerated heating issue? I would think that it would dilute the oil and take away it's ability to do the lubricating job it was meant to.

Could having too much oil and too much coolant have caused the heating problem. I personally don't think that would be accurate because if it was true then the problem would NOT have steadily progressed each week as it has done. Rather it would have been a very noticeable problem from the very beginning of the first oil change.

What I think happened is that as I rode each week more and more gas was entering the oil system and as more entered that system it broke the oil down even more so the heating of the bike continued to get hot quicker and quicker.

thank you for any input you can give sorry for the long story.

Sounds like you have a bad fuel pressure regulator. Have you noticed poor gas mileage since buying the bike?

wow, you even included a video. Very thorough answer.

I get about 126 miles on the bike before the low fuel light comes on. I don't know if that is good or bad. I think it works out to around 30-35mpg which seems fine to me with how hard I ride. And the bike seems to pull ride fine as well at all RPMs.

However, if this regulator is bad... how would it leak gas into the oil?

The heat issue seems normal to me. It doesn't sound like your bike acting out of the ordinary. Its possible you have been riding a bit harder or keeing the bike in higher rpms as you get use to the bike, which could cause it to heat up quicker. Its also possible it has just been warmer in your area. A few degree's can make a big difference. Stop lights and heavy traffic will have any bike's temp racing up and kicking on the fan if its hot outside. My bike will usually kick on at every stop light in high heat environments.

If the oil was being diluted by gas, the bike wouldn't run hotter and still run great. It may even run cooler as thinner viscosity fluids actually disapate heat better. You would have performance issues if the bearings were not given the proper lubrication, which would drastically hurt performance.

with that kind of mpg. Its doubtful your FPR is bad. BackDoc (just guessing here) was probably leading towards excessive gas blowing by the rings and entering the oil that way.

Heres a link to a recently discussed topic of gas smell in the oil.

https://cbrforum.com/forum/general-t...e-fuel-136075/

well, bike is in the shop for fork seals. I left a sample of the oil I just changed a couple days ago that had the gas smell. Hopefully they take a few minutes to give it a once over and see if anything is out of the ordinary. Otherwise, I will keep an eye on oil fluid level and see how things go for the next 3,000 miles or so.

If the oil level increases and smells like fuel again then that is really bad right? I'm sure if there is anything internal that allows gas to mix with oil then it can't be good and means a ton of money to fix. My fingers will be crossed that I'm just paranoid and nothing is wrong.

Yes if your oil level goes up by itself for any reason thats very bad. Any mods to the bike like a power commander? Either your running way too rich from a bad tune, a bad FPR, or the rings are shot and you have really exsessive blow by. The first two options are easy/cheap fixes, the 3rd is not if you can't do the work yourself and even if you can its still not easy.

Oil level should not rise unless there is a problem with oil pump or filter.
Gas in oil is usually from ring blowby. From your OP you said you overfilled crankcase during an oil change but "didn't drain the excess". Very bad. This put extra load on oiling system and rings by creating very high pressure. Foaming action of oil hitting crank. In extreme cases have seen bent cranks.

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