Odor vapors of oil

[rpaul]

Hi everyone,
I feel that when I pull the engine to 5-6-7,000 rpm, in the subsequent deceleration phase, I feel a smell rising from the bike, which looks like "oil vapors" from the engine, given the mileage above 130k, that the bike generates a lot of oil vapor is normal, but these vapors should be "eaten" by the engine itself, directly from the vents in the filter box !! could it be that for some strange reason the air makes them rise towards the pilot?
First of all the smell is unpleasant and in addition I think it is also harmful / carcinogenic, so I was wondering if, 1st: does it happen to someone else? and 2nd: if you have any idea how to eliminate it ??
Thanks in advance to anyone who answers me!

[S Barker]

Are you sure it's not coming from chain oil dripping onto the exhaust ?

[rpaul]

Are you sure it's not coming from chain oil dripping onto the exhaust ?

Hi S Barker, thanks for your reply!
If it were chain oil on the mufflers, you should feel more when stationary or going slowly, not at more than 100Km / h like it happens to me!
It is as if when the engine turns strongly, closing the throttle, the vapors that are no longer sucked in by the engine are shot towards me from under the handlebar.
It is very evident how the phenomenon appears and disappears when the accelerator is closed and opened.
The question is why? How can I avoid it ??
Thank you all!!!

[John J]

Your description seems to suggest a lot of crankcase pressure. I would start by looking in the air filter box to see how much oil is in there, a little can be normal but a lot could mean high crankcase pressure. The high mileage of your bike may mean the piston rings / cylinders are worn a bit which can cause high crankcase pressure.

[rpaul]

Your description seems to suggest a lot of crankcase pressure. I would start by looking in the air filter box to see how much oil is in there, a little can be normal but a lot could mean high crankcase pressure. The high mileage of your bike may mean the piston rings / cylinders are worn a bit which can cause high crankcase pressure.

Hello John,
thanks for your answer!
I think you are right, the filter box due to inconvenience, I haven't opened it yet, but if I take a long trip, when I stop from the vents near the stand 2/3 drops of oil always fall, following the tube, I think is the air filter box breather.
Obviously, the bike with the displacement it has and its power in performance is not noticed that the bands are not tight, but I think that is the only possible explanation.
Is there anyone else who has so many kilometers and has similar problems? Or other bikes of the same km are fine?
At this point, what do you recommend to do? Making a new engine costs as much as the used bike or maybe more!
Since the bike is running relatively well, is there no way to just eliminate the smell?
Thanks a lot to everyone!

[John J]

I think I would do some easy tests first to be sure before even thinking about a new engine or a rebuild. First make sure your breather pipes are not blocked, second check in the air filter box to ensure all is as it should be and lastly, if you can get access to a compression tester that would help prove the condition of the cylinders.

This parts view of the air box helps show where the breather pipes are that need checking.

https://www.bike-parts-honda.com/honda-motorcycle/1000-MOTO/VARADERO/2011/XL1000VAB/Frame/AIR-CLEANER/17MBTB01/F__1900/2/13823

[S Barker]

I misunderstood the description of the problem the first time I replied.

As I understand it now : After running the engine at ?? throttle for ?? long in ?? gears and then shutting the throttle with the bike still moving (overrun) at ?? MPH/KPH there is strong smell of oil vapour.

If there was a problem with piston rings or valves causing excessive crankcase pressure this would be highest when the engine was working hard.  On overrun with a closed throttle the crankcase pressure should drop and airflow through the filter box should be very low.

I don't understand why closing the throttle but travelling at the same speed in the same gear should cause oil vapour to be expelled unless the vapour was being sucked in by the intake system when the throttle is open and then has nowhere to go when the throttle is closed. In this case the oil consumption would be abnormally high ??

I suspect the most likely cause is a blocked or open vent hose. 

Is the bike an FI or Carb. If it's an FI there could be a problem with the PAIR system.

[rpaul]

If there was a problem with piston rings or valves causing excessive crankcase pressure this would be highest when the engine was working hard.  On overrun with a closed throttle the crankcase pressure should drop and airflow through the filter box should be very low.
I don't understand why closing the throttle but travelling at the same speed in the same gear should cause oil vapour to be expelled unless the vapour was being sucked in by the intake system when the throttle is open and then has nowhere to go when the throttle is closed. In this case the oil consumption would be abnormally high ??

Guys, thanks a lot to everyone for your interest and answers !!
I guarantee you that the smell is only there when the bike decelerates at high speed, today I noticed it again and that's it!
In my opinion, it does it because if the accelerator is open, the vapors are sucked by the engine itself, when I close it, the air that is entering the manifolds takes a "water hammer" (I hope you understand also translated) and comes back, dragging the oil vapors together ...
Yes, obviously it is a hypothesis, I have not ordered a new engine, so soon I will stop it for winter storage and I will take it apart calmly to check every part, in the meantime I wanted to get a clear idea of the problem, but I think it is something similar to what I suppose
the bike has carburetors.
Thanks everyone for participating

[S Barker]

So, does it use a lot of oil?

[rpaul]

So, does it use a lot of oil?

Hi SBarker, thanks for the answers!
In truth, not a lot given the situation, he will eat 2/300 ml of it every thousand Kilometers, it is not a little, but not a lot either.
But this is also a complex problem, if I'm not mistaken, there are 3 bands, two that hold the pressure, the third that acts as an "oil scraper", perhaps the sealing ones and the scrapers are relatively and good, so you don't eat oil, only shoots it from the vapors.
Thank you all!