Oil in the air box (my fault) - lack of power

[Dirk_S]

I was dumb and forgot that the V7 II only takes 2L of oil; I fed it 4L. The bike puked it out while I was filling, and I drained out the extra with a pump. Forgot to actually check the air box until just today, and noticed a lot of oil sitting under the air filter due to the overflow, as you all might expect.

After my rock garden escapade last week with the sidecar, I noticed that I’m dealing with some lack in power at higher speed. With the sidecar attached, I’m having trouble getting up to 70 mph. Without the sidecar, it can slowly reach 80 mph, but it seems to prefer around 70 mph without downhill help. I initially chalked it up to the worn clutch. After replacing the clutch, I do feel some positive difference in shifting, but I still feel there’s some lack of power, especially at higher speed and on an incline. I wonder if maybe some of this overflow oil may have gotten through. The air filter wasn’t wet but somewhat discolored all over.

My father mentioned about doing a compression test or leak down. Also wondering if the oversized 4.00-18 front tire might have something to do with it. Having a dickens getting the recalibration process completed.

Any ideas?

[fotoguzzi]

Dunno what’s up but surely a small block should go quite a bit faster than that.

[guzzisteve]

Yes,     Put oil down 1/4" from full on the stick, Remove airbox, run it WFO till it all blows out, Clean the mess, replace washed out airbox, return to normal.

Forgot, clean out throttle body, it may be full of oil

[Cam3512]

Wow, even with the sump spacer on mine I never put more than 2.5 liters.  Anything more would get puked out.  Drain everything to do it again, chalk it up to a brain fart.

[SmithSwede]

I agree.  Run it without an air filter briefly.  Clean out the oil.  Then replace the air filter with a new one.  I bet it doesn’t take much oil to severely restrict a small paper filter like that. 

[John A]

You ‘can’ replumb the breather drain to a bottle or overboard. The oil mist going into the air box can be detrimental to performance by adding its oil mist to the intake process. Just disconnect the line from the breather to the air box and put the end in a vented catch bottle or route it to drain so it won’t drip on rear brake or tire. Plug the fitting in the air box that you took the drain line off from.

[Bulldog9]

I didn't drastically overfill the oil, but found that running it at the FULL line caused about 1/4 liter to get puked out into the airbox and it soaked the filter and impacted performance. Clean everything out, oil at 1/2-3/4 on dipstick COLD and should be fine. May also want to spray some cleaner into the TB to clean it up if it sucked oil into the stepper/IAC ports.  How does the bike idle?

[Scott of the Sahara]

I did the same thing to my Ural. The extra oil went directly into the throttle bodies and made the engine run poorly. It would not idle and it had real problems maintaining 55MPH in top gear. I put a oil catcher in the breather and took out a bit of oil and now it is running pretty good.
I also ran some Seafoam through a couple of tanks. that seemed to help.