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Discussion Starter · #1 ·
This is more of an informational question than it is a real concern. Since I have owned my CX, I have always noted that the oil smells pretty strongly of gas. I am not overly concerned because comparing the drip rate off of the dipstick with the crankcase oil versus new oil out of the jug reveals that there has been no change in viscosity, and I have not had any problems with the bike on long runs. I did wonder after rebuilding the carbs and changing the oil & filter if the odor might diminish but that has not happened. Just curious - have any of you noticed this?
 

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You probably have raw gas (running rich)going down the intakes, and not combusting, mixing with the oil. What do your plugs look like? Black? How's your mileage?
 

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There are occasions when if the floats and float needle valves in the carb bowls have not been doing their job properly and or other faults with the carbs some fuel may be allowed to enter the engine at start up e.g raw fuel being sucked into the engine via the cylinders and not being ignited and working it's way down into the engine oil.

As you no doubt know Petrol/Gasoline is very aromatic so even a thimble full in the oil would smell like there's more.

Another way some extra fuel and fuel vapour can enter the engine is if there's a raw fuel blow-back into the Air-box and then this get sucked into the engine.



If the bike is running well just change the oil if it's due and the next time you clean the carbs make sure the floats etc are set-up correctly,



http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=19&t=110



but also clean out the Air-box and clean or renew the Air-filter now as a matter of course and remove the drain plugs and drain the drain pipes.
 

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Discussion Starter · #5 ·
Plugs look fine - tan. The carbs were rebuilt about 200 miles ago using Larry's book and an ultrasonic cleaner. The floats were set perfectly using a caliper. The carbs were balanced using a Morgan Carbtune. The lines off of the airbox are regularly opened and allowed to drain. I do think that I am overdue on cleaning the airbox, and the bike could probably use a new air filter. Looks like I have a project tomorrow. Thanks, as always, for the ideas and input.
 

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It's normal for a small amount of gasoline to make it into the oil but it usually gets evaporated off during any sort of rides where the bike can stay at operating temperature for at least a half hour. Of course as mentioned above gasoline has a distinctive odor and it only takes a drop, the smell also remains to some extent after it's evaporated.



A long time back I learned to fill up my car's gas tank BEFORE I took a shower prior to a date, just a little on your hand will stick with you for hours..
 
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