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K100RS Final Drive Mystery Tue Nov 04, 2014 1:21 am
brickrider
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Life time member
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Upon changing the oil in the 1985 K100RS' final drive, I learned there has been water intrusion. I can't for the life of me understand how/when.
As an airhead rider for decades, I'm well aware of the need to avoid high pressure water streams near the final drive vent on the top of the case. I always managed that without any problem on my airhead BMWs.
When I first acquired this motorcycle I changed all the fluids (among other things) and found nothing amiss. Now, about 12K miles later, the contents of the final drive looked like coffee with a healthy shot of milk.
I live and ride in an arid environment. In fact, I don't recall ever riding that bike in rain. During the few times I washed it, I was careful with the hose, yet there was water where it never should be. Can anyone offer an idea that would explain this? Are the vents on K100 final drives defective![Question](https://2img.net/i/fa/i/smiles/icon_question.gif)
As an airhead rider for decades, I'm well aware of the need to avoid high pressure water streams near the final drive vent on the top of the case. I always managed that without any problem on my airhead BMWs.
When I first acquired this motorcycle I changed all the fluids (among other things) and found nothing amiss. Now, about 12K miles later, the contents of the final drive looked like coffee with a healthy shot of milk.
I live and ride in an arid environment. In fact, I don't recall ever riding that bike in rain. During the few times I washed it, I was careful with the hose, yet there was water where it never should be. Can anyone offer an idea that would explain this? Are the vents on K100 final drives defective
![Question](https://2img.net/i/fa/i/smiles/icon_question.gif)