Jump to content

How to drain the airbox on a 2005 RT?


Recommended Posts


My bike is exhibiting all the classic need to drain the airbox symptoms, but I can't seem to find the drain. Any help?



I think BMW stopped putting drains in their airboxes some time in the 1950's; so you can't really "drain" it. You have to vacuum it out the top. I refilled mine with a mixture of 78% nitrogen and about 22% oxygen, and the bike now runs beautifully.

Link to comment

The symptoms are not unique to the RT, they include rough idle, miss-fire, and stuttering. The GS's and C's actually have a cap, similar to the oil cap, on the bottom of the box to make this a simple procedure. My R1100S has plugs that can be removed, but my RT seems to have nothing.


Over time, oil and water vapor from the crankcase breather collect in the bottom of the air box. The engine does not digest these non-vaporized fluids well, thus the need for to occasionally drain off the collected fluid. The only way I can see to remove this collected fluid from the RT is from the air cleaner side, which is a bit of a bother (pulling the plug is just a bit simpler than removing all that tupperware).

Link to comment

Pull the air intake snorkel and air filter, you can then wipe it out from there. To date though I've never seen any oil in a hexhead RT's intake.

Link to comment

Yeah, we noticed that earlier this year when Jamie was showing us how to drain the airbox (on Andy's GS I think), and so I wanted to know how to do it on my r12st. Suffice it to say, there is no longer a drain hole there.

Link to comment


This topic is now archived and is closed to further replies.

  • Create New...