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Bmw R18 oil leak

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themotomusafir

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There some oil as you can see in the picture. I presume there would be more as I have installed a skid plate, which I inted to remove today.

Also the bike is cold, and the sight glass doesnt show anything but when I level the bike the oil shows up little lower than half of red circle.

Anyone know what am I about to get into? Thanks.
 
Is your oil filter loose? Based on the pictures, maybe the drainplug for either the tranny isn't tight or the crushwasher wasn't replaced?

It's hard to peg if it's a seal problem based on the pictures because we have no source of the leak.
 
This seems to be the leak- air filter area. And also this is the oil level on a leveled bike (reading is after 6mins ignition turned on, and then 5 mins turned off)

When the bike is cold and on side stand, no oil is visible in the sight glass-
 

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I had the exact same issue at one point ... mine turned out to be a leak someplace at the filter itself ... replaced the filter with a new one and the problem went away .. I hope your problem as a similar simple solution to it.
 
Ulrich said:
I had the exact same issue at one point ... mine turned out to be a leak someplace at the filter itself ... replaced the filter with a new one and the problem went away .. I hope your problem as a similar simple solution to it.
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Do i need to drain the oil or just replace the filter.?
 
I didn't, I just put a pan underneath and pulled it ... some oil came out .. not too much ... and I just topped it off after ... but don't put in too much ... if you have a wheel choke put the bike in it ... put maybe 250 ml (1/4 liter) in it, warm up the engine and then let it sit in the wheel choke for maybe 10 minutes and let the oil drool down and check if it is anywhere in the little red circle you are good to go ... if not add another little bit , wash rinse and repeat the checking procedure and hope the leak went away.
 
Looks like a leaky filter. If you’re due for an oil change, now’s a good time to do it. Sometimes the gasket from the previous oil filter likes to stick to the engine block. Make sure when you unthread it, the gasket is attached to the filter.

Once off, clean the mating surfaces with a microfibre towel and some brake clean to insure a good seal.
 
Ulrich said:
I didn't, I just put a pan underneath and pulled it ... some oil came out .. not too much ... and I just topped it off after ... but don't put in too much ... if you have a wheel choke put the bike in it ... put maybe 250 ml (1/4 liter) in it, warm up the engine and then let it sit in the wheel choke for maybe 10 minutes and let the oil drool down and check if it is anywhere in the little red circle you are good to go ... if not add another little bit , wash rinse and repeat the checking procedure and hope the leak went away.
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Well when the bike is cold and on ths side stand the sight glass doesnt not show any oil. Once i level the bike, you can see the oil level almost covering majority of red circle..

This is based on cold bike reading.
 
themotomusafir said:
Well when the bike is cold and on ths side stand the sight glass doesnt not show any oil.
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try getting acquainted with the manual. There is also a maintenance guide in here that Ulrich put together which explains the procedure and other facts to keep things clear and simple with maintenance. You’ll have to search the forum as I don’t recall where it’s stickied.
 

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themotomusafir said:
Well when the bike is cold and on ths side stand the sight glass doesnt not show any oil. Once i level the bike, you can see the oil level almost covering majority of red circle..

This is based on cold bike reading.
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I think that is pretty much spot on ... run the engine warm and then let it sit for 10 minutes straighten it up and you should be somewhere in the middle of the sight glass.
 
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