Gearbox drained oil photo?

[JMitchell]

Aloha forum,

 

I just drained my 96 1100RT GB.  The bike has 55,000 miles.  8000 of which I have put on the bike in the last four years when I acquired the bike.  I changed the oil at that time but did not remember the sheen in the oil currently.  I have not noticed any changes in the GB in the last 8000 miles.  Not having compared this bike to another RT I am not sure of the normal noise of the GB.  I have noticed when at idle and the clutch is not engaged you can tell a difference in noise level then when the clutch is engaged.  Not sure if the normal for the RT.  The drain plug had the normal dark residue.  No noticeable pieces of metal.  I attached a photo of the drained oil.  I replaced the oil with Lucas conventional 85-140wt.  The gearbox is quieter at idle than before.  The shifting seems slightly smoother.

The previous oil used was conventional 85-90wt.

The FD oil was a clear as when I put the oil in.

 

Thank you,

-John

[dirtrider]

3 hours ago, JMitchell said:

Aloha forum,

 

I just drained my 96 1100RT GB.  The bike has 55,000 miles.  8000 of which I have put on the bike in the last four years when I acquired the bike.  I changed the oil at that time but did not remember the sheen in the oil currently.  I have not noticed any changes in the GB in the last 8000 miles.  Not having compared this bike to another RT I am not sure of the normal noise of the GB.  I have noticed when at idle and the clutch is not engaged you can tell a difference in noise level then when the clutch is engaged.  Not sure if the normal for the RT.  The drain plug had the normal dark residue.  No noticeable pieces of metal.  I attached a photo of the drained oil.  I replaced the oil with Lucas conventional 85-140wt.  The gearbox is quieter at idle than before.  The shifting seems slightly smoother.

The previous oil used was conventional 85-90wt.

The FD oil was a clear as when I put the oil in.

 

Thank you,

-John

 

Morning  John

 

I can't tell a lot from your picture but that oil does look to have a golden sheen to it. On the early BMW 5 speed gear boxes that usually indicates shift fork wear. 

 

Are you by chance preloading your shift lever prior to the shifts?   (that can wear the shift forks)

 

With you having a 1996 (assuming still the original transmission) those don't have much back-cut on the shifting dogs & gears so those do tend to allow the shifting parts to move around more as they want to ease out of gear when they are under load. 

 

If you are preloading the shifts then quit doing that, otherwise about all you can do is ride it until it starts jumping out of 2nd or 3rd gear. 

 

The above is assuming that gear oil has brass in it. As I mentioned above I can't tell all that much from the pictures. 

 

You can try straining that gear oil through a paper towel (with cold gear oil that will take a LONG time), then see what the paper towel catches. Take the paper towel out in the bright sunlight after all the oil goes through it to see if it is full of shinnies. 

 

 

[JMitchell]

Hello DR,

Thank you for your reply.  Not exactly sure what you mean by preloading.  If you mean do I apply pressure on the shift lever prior to engaging the clutch.  No I don't.  Part of the enjoyment of riding the bike is to finesse shifting through the gears smoothly.   I did save a container of oil and will drain through the paper towel.

Currently the BMW has never jumped out of any gear.

 

JM

[dirtrider]

1 hour ago, JMitchell said:

Hello DR,

Thank you for your reply.  Not exactly sure what you mean by preloading.  If you mean do I apply pressure on the shift lever prior to engaging the clutch.  No I don't.  Part of the enjoyment of riding the bike is to finesse shifting through the gears smoothly.   I did save a container of oil and will drain through the paper towel.

Currently the BMW has never jumped out of any gear.

 

JM

Afternoon  John

 

" If you mean do I apply pressure on the shift lever prior to engaging the clutch"-- Yes, that is preloading.

 

Well there really isn't much yellow metal (brass) inside the 5 speed gearbox so if that sheen you see is in fact brass particles then it is coming from the shift forks. On the early 1100 5 speeds that is typically from the shift dogs (shift collars) slightly backing out of engagement into heavier contact with the shift forks.  

 

Do another oil change in a couple of thousand miles to see if the new gear oil also has that bronzish look. 

 

If it is internal wear then not a lot you can do about it as parts for those early 5 speed transmissions are becoming difficult to find new & a trans overhaul including having the gears & collar ears back-cut is very expensive. (most just go with a later used M-97 from some place like E-Bay)

 

As long as it is is just brass in the gear oil (assuming that it is brass particles) & it isn't jumping out of gear while riding then just keep riding it until it starts jumping out of gear. It won't leave you stranded, they just usually keep getting worse & worse once they start jumping out of gear. 

 

 

 

 

[JMitchell]

Attached are two photos one from the GB and the other the FD to make a comparison.  There were no small pieces of metal in the paper towel just a slight discoloration as you can see in the photo.

I will change the oil in 2000 miles and check it again.  This bike has an interesting history.  It was purchased from a salvage yard not long after it was new.  My good friend purchased it as a restoration project.  It had been hit from the rear and the wheel was lying horizontal.  The engine ran and the transmission shifted through the gears.  I acquired the bike six years ago and has been solid mechanically since.  It had sat for 4 years before I got it so I enjoyed bringing it back to life.   Its the perfect year in that you can still wrench on it without to much challenge.

Some of the projects I have done consist of...  Valve adjust, Rocker adjust, TB sync, All oils changed, tires, paint, Wilber shocks (great addition) updated fuel injectors, crank sensor, computer mixture adjust, (this really helped the midrange RPM) misc small items to make sure everything works as it should.

 

In your opinion since I have not heard or road a RT other than this one does the GB make a fare amount of noise when idling.  When I first started the bike the TB were out of sink the GB much more noise then.

 

The shiny spots in the two photo's is the sun reflection.

 

Thank you,

-John

 

 

 

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[dirtrider]

11 hours ago, JMitchell said:

In your opinion since I have not heard or road a RT other than this one does the GB make a fare amount of noise when idling.  When I first started the bike the TB were out of sink the GB much more noise then.

 

Morning  John

 

That gearbox rattle at idle with the clutch engaged is pretty normal. 

 

The 1100 transmission is a constant mesh  transmission. That means the all the gears are spinning & meshed every time the input shaft is spinning. One gear of each gear-set is not connected to the shaft that they free-spin on UNTIL that particular gear is selected with the foot lever.   

 

With all the gears connected & spinning, plus the free-play between the gears, allows the gear sets to rattle at  idle. Plus the BMW boxer engine has very harsh combustion pulses at idle so that makes it seem even worse. 

 

If your 1996 1100 still has the original M-94 transmission then your transmission should actually have less gear rattle than later transmissions as BMW used damping "O" rings between the gears & shafts on those early transmissions. 

 

As far a what you caught in the paper towel, the no-chunks is a very good sign. I just can't tell much from the pictures as it doesn't allow telling original (normal)  oil color from brass contamination. 

 

If you want to spend a few dollars to know what is actually happening inside that transmission then give Blackstone Labs a call (or go to their web site) & have them send you an oil simple kit. Then next gear oil change send in an oil sample for testing. They will generate a report with what is actually in the oil & how much of each substance by precent is present. In most cases they will also tell you if the percentage you have is normal or abnormal.   

 

Blackstone Labs web site____     https://www.blackstone-labs.com/engine-types/motorcycle/

 

 

[Jim Moore]

I don't think I've ever seen one painted white before. That looks pretty cool!

[JMitchell]

Thank you DR,

 

Sounds like a good plan having the oil analyzed.  Sure like to get 200,000 miles out of this bike.  :-)

[Camhead64]

Looks like condensation in the oil not metal. Interested to see what an analysis indicates I love real data.