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Final drive leak repair question.....

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BER18 100

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R18 Anniversary Edition
Has anyone had leak repair done to a final drive on their R18? If so, is it simply a matter of a seal remove and replace?
I am thinking about a 180 mile one-way trip to a dealer to bring an end to the final drive leak. Was hoping for a 1 day in and out process i.e. an out patient arrangement.
 
I personally haven't experienced a leak (assuming from the drain plug); however, I can't imagine it being anything more than the O-Ring if leaking from the drain plug.....

Save yourself a winter ride and spend some time wrenching on your machine... Order a couple of new O-Rings and perhaps fresh fluids and perform the bevel gear fluid change and new O-Ring.. Follow the proper torque settings...
 
Thank you for that input. It seems to be coming from the great circle.

IMG_1814.jpeg
 
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Wow, there was a lot of info there.
Thank you.
My leak has the characteristic gear oil smell, so it is not just grease melt.
I’ll try replacing the o ring on the drain plug for starters
 
Maybe try the O-Ring and measure what you drain from the rear Bevel Gear drive, and compare it to the recommended amount.

Did anyone from the other thread state as to what the root cause or fix is for when oil is wicking out like in your picture?
 
Oldsldog told me he just took the bike to the Sarasota dealer and they fixed it for free.
My R18 is well within the warranty period so they should fix it.
 
Hello, i got the info from BMW service that final drive is slightly overfilled from factory. I had the same issue and they fixed it during last visit. They just put lower amount of oil.
 
Yup that's the story, but if you do have a leak it won't fix it. My ride had seal pinion seal replaced under warranty after trying lower fluid level first. The first repair wasn't performed properly and did not seal. It was done again by HAPS cycle sales in Sarasota FL. It is holding for now. I rode about 1500 miles since repair with no further problems. They have a knowledgeable young mechanic over there who is pleasant to work with.
 
Interesting that the factory would overfill that drive. Who else would know better?
I wonder if this final drive is vented? My R1200C was not vented, so I was careful to not overfill.
 
Interesting that the factory would overfill that drive. Who else would know better?
I wonder if this final drive is vented? My R1200C was not vented, so I was careful to not overfill.
Same here ... I overfilled my 'Chromehead' a bit and ended up with the same result as others has shown for the R18 ... it leaked and some of the oil ended up as 'Tiger Stripes' on the tire .. I completely disassembled it and found out that the seal was just fine ... put it back together and reduced the amount of oil slightly ... and the problem never came back ... Maybe BMW over fills it to make sure a bit comes out and the seal is properly lubed ... knowing the a lot of dealers will change the oil (with the correct amount) at the 600 mile / 1000 km service ... just my 2 ¢. ;)
 
I have my BMW r18 motorcycle under warranty due to an oil leak from the rear wheel differential. The motorcycle was delivered to the Autokraft dealership on December 18, 2024 and until the current date 01/28/25 is not ready, due to lack of spare parts. According to national laws, companies when marketing equipment in national territory must have a minimum stock for ready supply. This did not happen with BMW in Brazil for the R18 model. In view of this, a lawsuit is being filed against the factory.
 
I have my BMW r18 motorcycle under warranty due to an oil leak from the rear wheel differential. The motorcycle was delivered to the Autokraft dealership on December 18, 2024 and until the current date 01/28/25 is not ready, due to lack of spare parts. According to national laws, companies when marketing equipment in national territory must have a minimum stock for ready supply. This did not happen with BMW in Brazil for the R18 model. In view of this, a lawsuit is being filed against the factory.
Am I ok understanding that you purchased the bike on Dec 18th and so far you have not received the bike due to the leaking ?Can you not terminate the deal?
If I paid for something and it is not delivered I can walk away with my money back.
 
Drained 200 mL exact. I may have lost 10 mL.
Getting new o-rings today.
Yes on torque wrench.

When I removed the drain plug I had to really get on it. But the torque spec only about 20 Nm.

I’m thinking it was over torqued.
Funny the fill plug has higher torque spec!
 
A mechanic friend said not to use an oversized o-ring to stop a leak.
Each time I take out the drain plug it costs me $11, so advice welcome.

plu with large ring.jpg
 
Haven’t had issues with the R18 drain plug but my R9t plug was torqued by an angry elephant. The bolt stripped nicely and cost me $200 to get a professional to extract. Word of caution, check/ remove the fill plug before draining any fluid. IMG_3727.jpeg
 
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Ouch that does not look like a fun problem.

When I removed the leaky drain plug I had to get on it with a long handle ratchet to break it free.
Seemed odd that it would be on that tight. Am hoping that over tightening renders the o-ring useless which would explain the leak.
 
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