BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

Hi,

After a vigorous 75 mile ride Sunday (afternoon was hot, but lots of RPM anyway), I got off my bike with a cloud of smoke coming off the exhaust canister under the bike.
Fluid from somewhere was on the hot exhaust. The bike has no spots under it when parked, so I can't find any drips.
Seems it happened at high RPM? Anyone seen this?

I got a appt with a mechanic to look at it Saturday, just wondering if anyone knows this, and if I need to prepare for a major surgery.

thx

Did you check the oil level. Not too much oil? Too much has to go somewhere. Easiest way out is from the sump to the airfilter.
Open up the airfilter, take out the filter and check how much oil is at the bottom of the housing.
When the oil gets really hot ("a vigorous 75 mile ride, Sunday afternoon was hot, but lots of RPM anyway") ,
oilfumes from the sump are sent to the airfilter to be sucked into the cilinders when the engine is running.
But there is always some oil residu at the bottom of the air filter housing. It should be only a little bit.
If I remember correctly, there is a rubber line going from the airfilter housing down and it ends somewhere next to or above the exhaust canister.
That could be the problem, Clean the air filter housing from the oil residu.

Check the drain on the left rear of the airbox.

The drain plug is above the rear suspension preload adjuster. I had literally one drop come out recently after opening the plug. The plug does have an oil seal though, is it still in place?

If you have really been flogging it can produce some measurable oil in the well at the rear of the box. I always check at oil changing time and drain if there is any.

Normal ops usually doesn't produce any if the engine is in good nick.

A good track day will usually give a small amount. It has a "O" ring to seal.

thanks all. The bike was full serviced in April, and I check the sight glass before each ride, and it's always at 50% level. I have added no oil to the bike, and this season's miles are lower due to the enormous amount of rain here in the east.

It's stopped drinking oil about 20k miles ago, it has 54k now.
Probably a clogged witchamacallit... or maybe low anti freeze!

I will get in there and check it out... I had palpitations of something cracked or broken.

thanks again.
herb

herb,
What did the smoke cloud smell like? Gear, DOT4 or engine oil? They each have very distinctive odors, especially when they are smoking hot. My guess, because of the hot weather AND high RPM's, which creates additional heat, besides the very hot engine, from the transmission gear teeth meshing at very high speeds, is that it's gear oil leaking out the top transmission vent -or- past the transmission input shaft seal inside the slave cylinder cavity. The other possibility is that it is the DOT4 clutch slave fluid weeping from the slave piston bore, also because of the excess transmission heat.

FYI, I experienced transmission gear oil overheating many years ago in truck transporting my R1150R up a ~1.2 mile very steep uphill grade of a twisty mountain road , revving well over 4,000 RPM for 2+ minutes in 1st and 2nd gears of my Nissan pickup, to stay in the power range for each gear (2.4L 4 cylinder engine) around the sharp corners. I began to smell hot transmission oil fumes in the cab, so I pulled over to a dirt pull-off area to have a look-see. An underneath look revealed an oil stain weeping out the top where the stick shifter boot was. The transmission case was so hot I could feel the radiant heat from 2+ feet away! Touching the tranny case almost burned my fingers! OMG! time for a pit stop hood up cool off. It's a good thing it was very windy at the time near the mountain top. Truckers know high RPMs in the lower gears + a steep uphill + a heavy load = excess transmission heat . . . now we all know.

+1 on what Rob said especially concerning the transmission seal. You didn't say anything about the smell of the burning oil. On an '03 R I tried switching the tranny to synthetic at 18K. Shortly after I had oil slowly weeping out of the shaft seal and burning on top of the cat converter. Smelled like burning toast. BMW repaired and I didn't use syn again.

You mentioned a full service. Transmission too I assume? Any difference in the type of gear oil?

Since no one else has suggested it, when I had this experience, it was the rear shock leaking on the cat.

Thanks again all!

It appears it is engine oil, not gear oil. and it's only on the right side of the underside canister, the left side is sparkling clean.
looks like I got a crushed drain line on the right side of the case, where the clip that ties it to the case is.
It appears to be just old, and ragged, like me.
I do have a appt. tomorrow for a mechanic to look at it, and a skype call with a friend tonight to get a more accurate assessment.

does anyone know of a microfiche picture (or a personal pic!) of this hose? Can't seem to find it on bobsbmw.com in their library.

thanks again
herb

For the life of me I can't imagine what your seeing there. The cooler lines are all hard lines. All the oil passages other than that are? internal.

I'll be interested in what your wrench finds.

I'm betting on oil leak at pressure sensor.

sweatmark wrote:I'm betting on oil leak at pressure sensor.

does anyone have a pic/location of this sensor?

Disclaimer: I am not a mechanic! So I don't have those eyes!

I took the bike to Roland and The Spare Parts Company in Philly, and it turns out, the front top gear oil filler plug lost it's torque, and was weeping at high RPM. The weep was so light, the gear oil was not visible on the drive case itself, and only gathered on the exhaust can underneath.
(I didn't see it, and after a 15 mile ride over there, he didn't spot it at first look either.) This explains no spotting under the bike too.
The gear oil loss was minimal. It's been topped up, and a new crush washer installed.


Props and shout out to Roland, who has a small garage at the base of the Ben Franklin bridge, full of vintage Moto Guzzi, and BMW's, that he fixes/restores.

his cool PR video is here.
http://sparepartsco.us/


what a relief.

thanks all.


PS: He has a original owner orange 1982 R65 LS there for service, this bike was so cool. All our bikes started out like this....