r1200 gs adv 2011 transmission

[HLVAN]

I recently changed the transmission fluid(80/90 syn. lucas) and noticed it had turned very dark almost black.
Normally this fluid is a golden brown after 7-8k. Total miles on bike are 28,000.
Is this the first signs of a bearing failure,and how possible with such low miles.

Thank you HV

 

[deilenberger]

I recently changed the transmission fluid(80/90 syn. lucas) and noticed it had turned very dark almost black.
Normally this fluid is a golden brown after 7-8k. Total miles on bike are 28,000.
Is this the first signs of a bearing failure,and how possible with such low miles.

Thank you HV

If you're certain it was clear when it went in - dark/black is a sign that a seal on a bearing has given way and the grease in the bearing has been washed out.

How possible? Dunno - but rumors abound that BMW has been using Chinese bearings on lots of parts, dunno if ZF (maker of the transmission) has also.

 

[HLVAN]

Thanks Don for the reply. If the bearing has lost its grease, how long before failure? Should I stop riding the bike?
I do hear a whine once the oil has warmed. My confidence in BMW has been shaken.

Thanks again HV

 

[deilenberger]

Thanks Don for the reply. If the bearing has lost its grease, how long before failure? Should I stop riding the bike?
I do hear a whine once the oil has warmed. My confidence in BMW has been shaken.

Thanks again HV

I don't think anyone can answer that with certainty. Bearings were also lubricated by the oil used in transmissions ("open" bearings) - so it might never fail, but might just remain a bit noisy. Noise generally is an indicator of wear.

I'd consider having the transmission looked at. Tom Cutter does a lot of BMW transmission work, I believe there are others like Anton Largiader who might also be of help. Both can be found on the forum at times. It does require pretty major disassembly of the bike, so if you're not up for that - a dealer might be your best bet.

 

[141987]

Why not try it for a few thousand miles with Castrol SAF-XO and see what happens? That is the fluid recommended by BMW.

Also I think Castrol SAF-XO is 75W/90, which is different from what you have been using.

 

[beemerphile]

My understanding was that the seals protected the bearings during wear-in, and when they gave in it was no problem because the gear lube took over.

 

[HLVAN]

Thanks everyone for the information. I will keep riding being aware of the noise.The oil (Lucas 75/90 syn) had been recommended by the dealer,I changed it yesterday and will ride a few K before trying the Castrol oil. I dread the thought of going to the dealer but, as you said Don that may be my only option.

 

[deilenberger]

My understanding was that the seals protected the bearings during wear-in, and when they gave in it was no problem because the gear lube took over.

It certainly wasn't designed that way.. dunno where you understood this from but no bearing manufacturer would design a bearing with a seal that "gave in" intentionally.

 

[deilenberger]

Thanks everyone for the information. I will keep riding being aware of the noise.The oil (Lucas 75/90 syn) had been recommended by the dealer,I changed it yesterday and will ride a few K before trying the Castrol oil. I dread the thought of going to the dealer but, as you said Don that may be my only option.

If the whine starts getting worse I wouldn't delay going to the dealer. You don't want to damage other expensive parts of the transmission by having the bearing get really sloppy or even worse grenade and scatter metal shards around the inside of the transmission. I assume the magnet drain plug wasn't covered in shavings when you removed it..

 

[beemerphile]

It certainly wasn't designed that way.. dunno where you understood this from but no bearing manufacturer would design a bearing with a seal that "gave in" intentionally.

From one of the resident wizards...

http://forums.bmwmoa.org/showthread.php?40536-Use-Open-Bearings-Inside-Oilhead-Transmission

...The answer is really simple - and about as counterintuitive as they come. When I first heard about the sealed bearings I thought they were nuts, until I found out why they did it.

BMW Oilhead transmissions were exhibiting greater than acceptable early bearing failure rates. It took about three years but, as you surmised, they did eventually discover that metal debris from the break-in process for the gear sets was drifting about in the oil and when washed into the bearings was damaging the bearings. Thus the failures.

So, despite the fact that there is lots of oil in the transmission, they chose to use greased, sealed bearings so as to keep any tiny metal particles out of the bearings during break-in.

After a while, and all of a sudden, those folks who use blue or red, and particularly synthetic gear oil will discover that their gear oil has turned a muddy brown. It's harder to notice if you start out with brown gear oil, but I digress. The source of the brown is some of the grease getting past the seals and discoloring the oil. As far as I have been able to tell, at this stage it doesn't matter because where grease washes out oil gets in.

But by this time gear mesh break-in is essentially complete and the amount of metal sloshing in the oil is almost nothing. So the bearings still stay healthy.

Those who check the magnet regularly, starting with a new bike, detect substantial metal fuzz the first couple of oil changes but not much after that. Break-in!

 

[deilenberger]

Interesting. If Paul sez it - that's good enough for me.

 

[HLVAN]

I did not see any metal fillings on the magnet or in the oil. After warming the oil on a short ride I noticed that in 4th gear ,4000 rpm and higher, the whining is most noticeable . In my thoughts I keep in mind a thread that was posted ,the person ignored the noise until he was on the side of the road. AS you posted Don ,transmission had to be replaced.

 

[Coma]

It might be worth a used oil analysis. Put few k miles on it with new oil. If the noise persists or other symptoms show earlier, you have your answer. If not then pull a sample and test. You'll know quickly. Wear metal should show quickly for a transmission that's eating itself.

 

[HLVAN]

It might be worth a used oil analysis. Put few k miles on it with new oil. If the noise persists or other symptoms show earlier, you have your answer. If not then pull a sample and test. You'll know quickly. Wear metal should show quickly for a transmission that's eating itself.

Thanks Coma for the info. I will check with my dealer and see who they recommend. Hopefully the noise gets much louder before self destruction. I am going for a short 300 mile trip tomorrow.