One of the resources in the download section, the BMW K100RT Routine Maintenance Manual, indicates that the amount of gear oil required is 850cc +50cc. Is the +50cc the amount between the min and max when checked with the dipstick/wrench? Also, I have seen recommendations online for either 75w90 and 75w140. Any thoughts as to which is best? When making a recommendation on weight of oil, I should mention it is coming to winter here and I will be driving all year. Winter gets to down to +1 or +2 degrees C. Any colder than that and the roads are too slippery to ride.

Thanks in advance,

I am using the 75/140 synthetic, our temps. may not dip as much as yours do but the oil had been recommended by some on the Flyingbrck.de website, it seems as they do experience similar temps. as yourself.
So far after 3 years I have not experienced any problems with the oil, to me the box is a little quieter.

Hope this helps  

ungaas wrote:I am using the 75/140 synthetic, our temps. may not dip as much as yours do but the oil had been recommended by some on the Flyingbrck.de website, it seems as they do experience similar temps. as yourself.
So far after 3 years I have not experienced any problems with the oil, to me the box is a little quieter.

Hope this helps  

Thanks. That helps a lot. 

Check around, there are other threads on the subject of gearbox oil.

I had originally used a Valvoline 70w-90w and after about 300 miles began to experience mis-shifts. Have switched to the Castrol and it's been smooth sailing ever since.

Castrol is even recommended above the much-vaulted Redline oil, so if you can get it up North where you're at then that's the way to go. :arrow:

Hi there, I tried the 75/140 synthetic, but had trouble with the seals, returned to the old fashioned original spec, so far so good

Best regards

JAP

japuentes wrote:Hi there, I tried the 75/140 synthetic, but had trouble with the seals, returned to the old fashioned original spec, so far so good

Best regards

JAP

In my reading on the net is seems there is some suggestion that pre-91 bikes have a problem with synthetic and post-91 seem fine with synthetic. Where does it leak out? Was it simply a matter of switching back to non-synthetic or was more involved?

Forget the synthetics cause leaks that may have been true when they were first introduced some 20 years ago but not nowadays it is an urban legend.
Regards,
K-BIKE

Hi, it was a small leak, you could feel the oil by the test hole and it would take a couple of weeks to form a drop. I drained the box filled and flushed with mineral oil and filled again.
Best regards.
JAP

japuentes wrote:Hi, it was a small leak, you could feel the oil by the test hole and it would take a couple of weeks to form a drop. I drained the box filled and flushed with mineral oil and filled again.
Best regards.
JAP

Well went to 4 places in town for gearbox oil. Only two available were Lucas Oil 70w90 and Bardahl 80w90 at the local dealer. Both were Dino. Went with the 80w90.

I have been running Shell mineral oils in all my machinery for the last 30 years or more in some cases. I have run them in very dusty and dirty conditions, raced in many forms done probably over a million miles and have never had a failure due to oil in all that time. Had a few due to lack of oil but not the oil itself and for the on road machines have had only 2 or 3 failures in any form.
As with anything else its regular maintenance that pays.
Synthetic oil has many good properties but only ever stands out in extreme circumstances like endurance racing and where you are running the engine and drivetrain on the edge.
For riding and driving in everyday circumstances that 99.99% of people experience the properties that makes synthetic oils so much better are never experienced and using them just gives you a feel good moment that you are doing the absolute best for your fine bit of machinery while you throw money down the drain and make the oil companies richer.
Use good quality mineral oil and put the extra $30 that you save into fuel and enjoy a 300km trip on the bike.

V

RicK G wrote:I have been running Shell mineral oils in all my machinery for the last 3 years or more in some cases. I have run them in very dusty and dirty conditions, raced in many forms done probably over a million miles and have never had a failure due to oil in all that time. Had a few due to lack of oil but not the oil itself and for the on road machines have had only 2 or 3 failures in any form.
As with anything else its regular maintenance that pays.
Synthetic oil has many good properties but only ever stands out in extreme circumstances like endurance racing and where you are running the engine and drivetrain on the edge.
For riding and driving in everyday circumstances that 99.99% of people experience the properties that makes synthetic oils so much better are never experienced and using them just gives you a feel good moment that you are doing the absolute best for your fine bit of machinery while you throw money down the drain and make the oil companies richer.
Use good quality mineral oil and put the extra $30 that you save into fuel and enjoy a 300km trip on the bike.

Thanks Rick

Hi there, in my opinion Rick just nailed it.

Best regards

JAP

Well changed the gearbox oil and final drive oil. New crush washers to be safe. Small amount of particulate on the magnetic plugs. Will probably upgrade to the stronger magnet versions from Beemer Boneyard next time. The only hitch was inadvertently moving the tinfoil I had carefully placed to ensure the centre stand was not covered in oil. Noticed it when about 500ml was pooling on the garage floor. Doh!!!!

Any suggestions for a cleaner to be used in the garage for small spills of gas/oil?

kitty litter

charlie99 wrote:kitty litter

Thanks. I did that.

I used to take my bike to an independent mechanic who mainly worked on R-series and Harleys. He used to have a liquid that he would spray on parts during oil changes etc. I presume that it was some kind of de-greaser or soap solution. It was in a tin with a pump to pressurize the dispenser. Unfortunately, he has moved away and I cannot enquire.

Tried Fracking ---that didn't work either. 

Jeyes Fluid  - excellent degreaser  
  

Hi there, around here we use kerosene, but I know a couple of guys who uses gasoline.
There is also a, nonflammable, environmentally friendly,  canned foam, by the brand cardoc but it requires a lot of elbowgine to work so I favor the kero.
If the oil stained floor is porous then perhaps a carpet is in order
Best regards.

JAP

japuentes wrote:Hi there, around here we use kerosene, but I know a couple of guys who uses gasoline.
There is also a, nonflammable, environmentally friendly,  canned foam, by the brand cardoc but it requires a lot of elbowgine to work so I favor the kero.
If the oil stained floor is porous then perhaps a carpet is in order
Best regards.

JAP

I worked at a garage and had to clean the oil up with kero and a broom. Followed by petrol and a broom. Followed by detergent and a hose.
Not always possible in a home environment, but it did work well.

When Charlie and I were taking the cylinder heads off a few weeks ago some a heap of black oil spilled on the floor so I used a spraycan of degreaser and kitty litter and it is now the cleanest bit of the floor.

Just changed Final drive and gearbox oil....easy peasy and the difference to gear change is amazing...no missed changes false neutrals and may even be quieter....


managed to not lubricated the centre stand springs by warping a funnel with the plug almost out.....undo by finger.
and by the way on special at Super cheap at the moment...$30 ish.....Rossco want yours done I have some left over as it only took 850ml and 260ml.