Final Drive question

I know this has been around but there seems to be a number of different answers to the same question.

I have a 2007 R1200RT, with 12,000 miles which I bought new.

I am about to change the final drive fluid and do an oil change myself. I have watched the videos but I still have some questions. my questions are:

1. What is the capacity of the Final Drive?

I have read figures on these boards that can't all be correct (80ml, 180ml, 240ml)

2. Is the "vent" hole the top level of the oil for the gauging the correct fill level? (like a car's diff for example)

Somewhere I read it is merely a vent for draining and that fluid should be replaced through the speed sensor hole.

3. As a follow up to the above question; if it is the level check indication, what is the correct orientation of the paralever to check the oil level? (eg. on the center stand? with the wheel on and the suspension at static sag?, etc.?)

4. When greasing the driveshaft splines should the driveshaft be removed and the front splines that go into the back of the engine be greased also?

5. What is the recommended gear grease type for the splines?

6. For an engine oil change, is motorcycle specific full synthetic (4T) 20w-50 the correct weight?

7. What is the correct oil for the Final Drive?

I was thinking of using Valvoline 70w90 full synthetic.

Afternoon aero_nautical

1. What is the capacity of the Final Drive?

I have read figures on these boards that can't all be correct (80ml, 180ml, 240ml)--- The latest data is: For initial filling (after an overhaul)it is 200 ml--- For just changing the gear oil it is 180 ml.

2. Is the "vent" hole the top level of the oil for the gauging the correct fill level?

Somewhere I read it is merely a vent for draining and that fluid should be replaced through the speed sensor hole.---NO, the fill hole & the wheel sensor hole are way above the correct gear oil level.

As a follow up to the above question; if it is the level check indication, what is the correct orientation of the paralever to check the oil level? (eg. on the center stand? with the wheel on and the suspension at static sag?, etc.?)---Just add the 180 ml & call it good. There is no good way to check the oil level.

4. When greasing the driveshaft splines should the driveshaft be removed and the front splines that go into the back of the engine be greased also?--On the 1200RT you have to remove the entire rear swing arm to get the drive shaft out so greasing the front is not usually done as it is a BIG job.

5. What is the recommended gear grease type for the splines?---BMW recommends Optimoly TA.

6. For an engine oil change, is motorcycle specific full synthetic (4T) 20w-50 the correct weight?---It can be, you need to look in your riders manual to choose the correct oil type & weight for the operating temperature that you ride in.

7. What is the correct oil for the Final Drive?---GL-5 gear oil that meets BMW's specifications.

I was thinking of using Valvoline 70w90 full synthetic.---As long as it meets BMW specs then it should be fine, if it doesn't meet BMW specs then I wouldn't recommend using it.

Thanks ever so much for answering my questions. That clears up everything but one question:

GL-5 is available in both 75w-90 AND 75w-140.

Do you know which would be the viscosity of the factory oil, or at least what a dealer would put in?

Thanks for your help

Morning aero_nautical

Back when your bike was sold the gear oil (suggested) by BMW was Castrol SAF-XO, that is a 75w90 long life gear oil.

Castrol SAF-XO is difficult to find in the US but can be found with some work. A close equivalent to the SAF-XO is Castrol SYNTRAX LONG LIFE 75W-90 (the NON LS, or NON limited slip, version.

In any case you want 75w90 long life non LS (non limited slip) gear oil.

It should be noted that when BMW was recommending long life gear oil they also thought the factory fill was lifetime. That's changed so I don't think you need to concern yourself with that.

Home Depot and probably Lowes sell a syringe for measuring and mixing 2 stroke oil. Something like that to push the oil into the final drive would make the job faster, easier, and more accurate. Make sure you don't lose any washers/spacers from the speed sensor. If you do the tip can contact the ring in the final drive.

Through experience I'm sure that if you ever ride through water that comes at least half way up the final drive you should change the oil as soon as possible. The final drive heats up as you drive and can expel some air past the seals. When it gets chilled by the water it sucks water in past those seals. I'm on my third final drive on this bike plus one was replaced on my 2006 GSA. All of these occurred shortly after fully immersing the final drives.

It should be noted that when BMW was recommending long life gear oil they also thought the factory fill was lifetime. That's changed so I don't think you need to concern yourself with that.

Morning Pat

Actually BMW recommended long life gear oil well after the factory fill-for-life era. The late hexhead service manual clearly has service data for changing the gear oil (including a drain plug on the final drive) but STILL recommends long life gear oil.

If it was only for the fill-for-life era bikes then why would they even have a gear oil recommendation as it wasn't intended to ever be serviced.

Gentlemen,

I thank you. What a amazing resource for sharing, and benefiting from, the wisdom of so many talented people.

Again Thanks!

Morning aero_nautical

The thing to keep in mind is: you can really afford good quality gear oil as you will get over 5 (not quite 6) oil changes from a single quart of gear oil. So even at $45.00 a quart it costs less than $10.00 per gear oil change.

Personally I change my final drive gear oil at every rear tire change as I already have the muffler moved & the rear wheel removed.

Good advice I'm sure, especially; since there are so many failures of this unit.

Thanks Again.

Good advice I'm sure, especially; since there are so many failures of this unit.

 

Morning aero_nautical

Unfortunately most 1200RT final drive failures are caused by the crown bearing failing. On the 1200RT the gear oil really has little effect on the crown bearing life as the crown being operates in it's own sealed-off chamber using it's own sealed-in grease.

The gear oil type & viscosity can have some effect on gear tooth wear but gear contact wear is usually not an issue on the 1200RT. Gear oil can also have an effect on seal leakage & that is probably the biggest reason to use the proper gear oil & keep it changed at reasonable intervals.

I'm fairly new here but I think I share everyone else's sentiments. Thank you knowledgeable people who unselfishly contribute your time and expertise.

I forgot to mention. I precisely measured the oil that drained out. There was almost exactly 250ml. That is way off what I have read I should put back in.

I'm going to bump this thread which I was reading in preparation for installing a new FD on my 2009 RT. ( Original failed at 27,000 miles right after flange recall and replacement. )

So my question is: BMW reduced the amount of FD oil from 220-240 down to 180 because the sealed housing needed space for the oil to expand when it got hot. When the Gen 2 FD came out with the vented housing, how come they didn't just go back to the original volume of oil since pressure would no longer be an issue?

Al

I'm going to bump this thread which I was reading in preparation for installing a new FD on my 2009 RT. ( Original failed at 27,000 miles right after flange recall and replacement. )

 

So my question is: BMW reduced the amount of FD oil from 220-240 down to 180 because the sealed housing needed space for the oil to expand when it got hot. When the Gen 2 FD came out with the vented housing, how come they didn't just go back to the original volume of oil since pressure would no longer be an issue?

 

Al

Morning Al

Good question--

Possibly because BMW found that the 180cc is, & has been, working just fine. That also keeps the fluid level below the seal when parked.

Or possibly BMW engineering didn't think the new membrane type vent would vent fast enough under some conditions.

I believe the initial (factory fill) is something like 200cc with the refill at change being 180cc due to not all gear oil draining out.

I guess I can see BMW's side as changing the re-fill amount could lead to confusion when it comes to what 1200 bike holds how much.

Lower oil level, less "windage", in turn causing less hp loss and lower operating temp. Of course, too low, big issues!