oil drip from throttle body?

[tufty1909]

My 2002 1150 has developed an oil leak from the left hand throttle body, noticed it last week after a day covering 500 miles, cleaned oil off but is reappearing after riding bike.
Anybody got any ideas.

Thanks Tufty

 

[Keith Chapman]

Have a read of post #5 on this thread

http://www.ukgser.com/forums/showthread.php?t=100430

 

[Number8]

My 1150 used to do this when riden hard (trying to keep up with a well ridden zx6r)

but mine has got 138000 miles on it

its was blowpast presurizing the crankcase and blowing oil into the airbox and being sucked into the motor , but as i said thsi was after a 150mile ride where te revs rarely dropped below 6k and the bikes been well used and abused

be worth tho seeing if the airbox has any oil in it , easy just on the left rear bottom of the airbox is a drain plug , like an upsidown oil filler cap , turn it through 90deg and it comes off ...

If oil comes out u have a prob , if it dosent the oil is coming from a rocker cover

 

[tufty1909]

However, I have some good news. Yesterday on my way home I stopped by the BMW dealer and while I was waiting for the salesperson to get the part no, a mechanic came to fetch some parts and I ride my luck and asked the question, He said that he has came across cases where the fuel can damage the o rings on the throttle valve stub pipe. I removed (badly stretched and fragile looking) o rings, cleaned and (carefully) replaced both sides and happiness!! This morning I arrived at work with no markings on the left pipe of my pants, yeah!! 10 Mins work and less than 4 UK pounds in spares....

Had a look at O rings found them to be stretched and one was broken, have ordered replacements.

be worth tho seeing if the airbox has any oil in it , easy just on the left rear bottom of the airbox is a drain plug , like an upsidown oil filler cap , turn it through 90deg and it comes off ...

Took drainplug out and a cap full of oil came out, and there is a small amount of oil in the throttle body tracts.
Does this mean rings have gone or valve guides knackered. Bike has done 17500 miles.

My 1150 used to do this when riden hard

This problem appeared on mine after a hard day.

 

[Burfcontrol]

Hi Tufty

Took drainplug out and a cap full of oil came out, and there is a small amount of oil in the throttle body tracts.
Does this mean rings have gone or valve guides knackered. Bike has done 17500 miles.

Look for the simple fix first - most likely overfilled oil once or twice, this is normal cause of oil in the airbox. Once it's there it'll get drawn into the inlet tracts of the throttle bodies. Looking at mileage of bike this is more likely cause vs rings or guides IMHO.

Cheers Jim

 

[Paul Young]

Please don't forget, guys, that this is a boxer engine. The pistons both move outwards together, then inwards together, so the crankcase volume (the amount of space inside the crankcase & behind the pistons) increases & decreases by 1130cc on every stroke. Take the oil filler cap off while the engine is running & you'll feel it blowing out the hole (like you've blown a head gasket). This air has to go somewhere or the crankcase would pressurise & the pistons wouldn't move properly. It goes into the airbox & if ridden hard, will be oil saturated. It then goes into the engine with the air/fuel & gets burned but some can flow down the inlets & drip out of the balance nipple under the throttle bodies.

HTH,