BMW R1200RT/R1250RT Forum

Oil changes continue to be a problem. (R 1200 RT, 2008)

1. empty oil
2. put in 4 quarts
3. ride away

should be the routine. It's not.

on the BMW... there's that little round window... I thought I understood how it works. I obviously do not.

I've noted that if I check the oil, on the stand, at night, when it's dead cold, and it's at 52%, ...
the next day when I ride it, park it on stand, wait 5 minutes, and check the oil window, it reads 60%...
that's acceptable...

So this oil change i thought i would..
1. drain the oil
2. put in four quarts new
3. check the oil in the round window
4. add/remove oil until 52% in window

because I knew that when it's dead cold at 52%, riding it and checking it the proper way produces a 60% reading.

So this morning, put it up on the stand cold, drain it, secure the drain plug, and start filling with new oil until 52%...
As I went, I noted that the oil level never showed up in the round window. Hmmm... what does this mean???
OK, keep going and put in all the oil from the 4 qt container.
Still NO oil level in the round window.
Add more from a secondary container.
NO reading.
Realize I've probably put in too much.
Start it and warm it up to about half normal hot.
check oil window... OIL level in window 100%+!

I've drained it all again and have 4 qts of new oil to work with... so now it's back to the Clymer Manual to see what the steps are there.
I plan to put in 4qts exactly, ride it around the neighborhood until normal hot, then park it on stand, wait 5 minutes, the check oil level in round window. I think that's the proper way.

I'm really disappointed the round oil window doesn't show the oil level in real time when cold. Really? I pour oil in and it just never shows up in the round window?
What makes the window show the oil level then? How can I trust it?

I know oil changes are ROUTINE for many of you, and that's the point.
I haven't hit on a set of steps that produces a desired result... in short, a ROUTINE.

If you'd care to share your steps in your routine, I'd be much obliged to see them.
Also, was there ever a year when the oil change routine became sensible? If so, what year was that?

Back to the Clymer manual!

Sincerely,
frustrated BMW jockey!

The Clymer service manual confirms that you can't check the oil level in the window unless the Thermostat (whatever that may be) has opened ... something so that the window reflects actual oil level.

The window does not behave like a fish bowl and immediately show more oil if you add more.

I started over, put in exactly 4 qts, rode around for normal temp, up on cstand, five minute check and... I can't read the oil window well enough to see what's going on. It's either 0% or 101%...

I added just a small hand pour of oil and did it again. Still can't read the oil window... BUT the LCD shows a check mark next to the word oil when you rotate through those items on the LCD. That will have to do. All I can do now is carry oil with me (I do that anyway) and wait for that little LCD panel symbol that means the oil is low. I can then stop, add a small amount, and wait for the check mark to re appear.

Yes, I'm aware that the "breather" tube (whatever that may be) will suffer if I add too much oil... but that's the problem. Ive yet to discover a reliable way to KNOW when you've added too much. Doesn't the engineer who designed the engine know EXACTLY how much oil it should start with? Seems like that's a thing he would know ... and maybe tell us so we could put that in THAT amount and not worry...

So it looks like the only reliable routine for an oil change (for me) is to.....
1. drain it
2. fill it
3. wait for the oil check mark on the LCD panel.

That's an oil change.


I hope smarter, more capable, riders will have a better experience.

I always drain the oil whilst the engine is worm/ hot that way the oil flows well and I get most of it out. Change the filter then re fill with a little under 4 ltrs of new oil run the engine gently make sure there are no leaks, then switch off and let the oil settle for 5 mins or so then check the window and adjust as necessary. Check again after a short run.

If you are unsure how much oil to refill with then maybe you need to check measure the volume of oil removed before adding the new oil in the same quantity

the oil sight glass is sh1t. its too low, too small and impossible to read accurately

IMO, it's honestly not that critical. If the level is anywhere on the sight glass it's not going to cause any harm to the engine. I get it in there but in the lower half (after a short idle to fill the dry oil filter and drained passages). When the engine gets hot and the thermostat opens up, starting flow into the oil cooler (for older bikes), the level can come up a bit. Check it again after a nice ride and tweak it for 1/2 to 2/3 up the glass. I usually shoot for 1/2 but again, it's just not that critical. If it's anywhere from 1/4 to 3/4, good enough.
I actually really like sight glasses, way better than dipsticks, it's easier to check periodically. I'm down looking under the bike at least once a week anyway just as part of routine mechanical inspection.

exportman wrote: Thu Aug 28, 2025 6:38 am I always drain the oil whilst the engine is worm/ hot that way the oil flows well and I get most of it out. Change the filter then re fill with a little under 4 ltrs of new oil run the engine gently make sure there are no leaks, then switch off and let the oil settle for 5 mins or so then check the window and adjust as necessary. Check again after a short run.

If you are unsure how much oil to refill with then maybe you need to check measure the volume of oil removed before adding the new oil in the same quantity

That's IT!
Those two things:
1. change oil when hot so the thermostat allows window to show level
2. measure what i took out and put the same amount in.

Strat Tuner wrote: Thu Aug 28, 2025 5:12 pm 2. measure what i took out and put the same amount in.

That runs the risk of shorting the oil if you start leaking or burning oil.

I am incredulous at the over thinking here.
Just follow manufacturers instructions...if it says put in 4 after draining, just do it.
Close it off and walk away or ride.
Yes, it is that easy !!

Go ahead and put in 4.0 liters/quarts ....

and the little round window shows that you've over-filled it. The oil level show well over 100%

I wish it WERE as easy as you described. It's not...

but I've sold it now ... it's gone forever...so that's not my problem anymore.

Shuswaper wrote: Fri Aug 29, 2025 8:45 pm I am incredulous at the over thinking here.
Just follow manufacturers instructions...if it says put in 4 after draining, just do it.
Close it off and walk away or ride.
Yes, it is that easy !!

Yeah, of the 20+ bikes I've owned throughout my riding career my RT is literally the easiest to do a oil change.

I fully agree with the reply made by jrr626 .I do an annual oil change and this year will be it's 19th oil and filter change ive carried out. So stop stressing yourself if the level is between the low and high on your weekly oil check, you're good to go you do not have to keep the oil level above the centre of the sight glass.Always checked after 5 to 10 minutes while the engine is still hot after a lengthy ride not just a quick spin around the neighbourhood .When I carry out an oil and filter change I always fill less than the 4l required by approximately 100ml then take it for a ride check on return, adjust if required while the engine is at full operating temp.

R1200 2008 sold. ...

Maybe next time, something used with LED lighting and NO CanBus!
oh yeah, something where you can change the final drive oil without removing the rear wheel!
1250? Maybe....

What was the best 1250 year model? (If I may ask...)