Oil in cylinders

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barryh
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Joined: Fri Oct 01, 2010 12:30 pm

Re: Oil in cylinders

Post by barryh »

A small amount of oil in the intake is normal just not the amount you have in the cylinders.

What level are you running the oil at on the dipstick ? You say it's never been above max but most people run about halfway. It was even sanctioned by BMW as a cure for oil consumption. Citing concerns with oil churning and breather loss a service bulletin was issued saying don't add oil until it reaches the min mark and then add no more than 1 pint which is another way of saying don't run above 1/2 way.
barry
Cheshire
England
Shades
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Joined: Thu Jul 20, 2017 1:20 pm

Re: Oil in cylinders

Post by Shades »

Thank you for your reply Barry !
I know about the crankcase volume issues and will check oil level later. I would like to install a deeper oil pan at some point but I will then need to change the center stand for a newer one with only 1 cross tube or what you want to call it ?
The '81 on models, have a deeper pan than the 77 right ?
But will the oil pickup need a spacer as well ? Is a aftermarket extension a better solution ?
Last edited by Shades on Sun Sep 10, 2017 6:53 am, edited 1 time in total.
barryh
Posts: 730
Joined: Fri Oct 01, 2010 12:30 pm

Re: Oil in cylinders

Post by barryh »

According to Anton Largiader a 77 already had a slightly deeper pan but it was deepened further in 81.

http://www.largiader.com/tech/oilpan/
barry
Cheshire
England
Shades
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Joined: Thu Jul 20, 2017 1:20 pm

Re: Oil in cylinders

Post by Shades »

Just found the same side, and he says the 81 is even deeper. My brother have a 81 RS and have a different center stand
Rob
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Joined: Thu Feb 13, 2014 2:05 am

Re: Oil in cylinders

Post by Rob »

I glanced through, but didn't see anyone suggest that you run your oil level at about the 1/2 way point between the high and low marks on your dipstick.
Measure it with the dipstick resting on the case, not screwed in.
Rob V
Shades
Posts: 19
Joined: Thu Jul 20, 2017 1:20 pm

Re: Oil in cylinders

Post by Shades »

Hey Rob ! Thank you for joining, it was mentioned and I am aware of the fact.

I took the carbs and air filter off and found oil in both intakes. The right carb is soaked in oil and the right side intake albow is soaked as well.
It seems weird since its the left side cylinder that contains the most oil and smokes... The left albow and carb is not fouled by oil ...

And yes I have to much oil in the engine
Wobbly
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Joined: Mon Aug 07, 2017 8:48 pm

Re: Oil in cylinders

Post by Wobbly »

Shades wrote: Sun Sep 10, 2017 4:41 am So yes the oil must be from the intake. But why would it almost stop smoking when hot ?
"The simplest explanation is usually the correct one."
- Ockham's Razor


It's a documented fact that most European countries are inhabited by magical little creatures which go by different names in various locales... leprechauns, faeries, hobbits, etc. You obviously have one living in your air box, who redirects the oil flow on an as needed basis.

You're so lucky to live in Denmark. In the USA we only have "Bigfoot". :lol:
After 20 years as a professional bike mechanic and 30 years as an engineer I know just enough to be dangerous !
ME 109
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Joined: Tue Aug 03, 2010 3:00 am
Location: Albury, Australia

Re: Oil in cylinders

Post by ME 109 »

If that much oil was getting into the cylinder when the engine was running you wouldn't see for smoke.
I think the oil gets into the cylinder when the engine is stopped, somehow.

A thread in ADV recently covered the same oil situation. I don't think a caused was found, but some interesting things showed up in very clear pics of the head, piston and cylinder.
Lord of the Bings
User avatar
Zombie Master
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Location: Vancouver Island BC Canada

Re: Oil in cylinders

Post by Zombie Master »

Shades wrote: Sun Sep 10, 2017 4:41 am Forgot to say I checked the rings in the bore and the end gap measured as new. Could the cylinder be distorted but still have good compression?

I am starting to feel silly, I can see in my own picture of the intake that there is oil in the rubber mount ....! So yes the oil must be from the intake. But why would it almost stop smoking when hot ?
Because it is up and running? The oil is burned like a two stroke?
Any and all disclaimers may apply
Shades
Posts: 19
Joined: Thu Jul 20, 2017 1:20 pm

Re: Oil in cylinders

Post by Shades »

So wobbly you think there is a nisse (great danish word for gnome!) in my air box high on fumes? So if I use pod filters it will all go away ? :)

I really can't figure out how to get to the breather valve with the starter assembly in the way and I can't find a good way to take the starter off. My manuals all describe this with the engine out of the frame. I think I once saw a guide to the complete reed valve modification on the older airheads but now I can't find anything about it. Is it possible to take the starter off the engine without dropping a gear or something into the hole to the flywheel? Remember, I am used to Japanese bikes!
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