Boy, are we embarrassed. We posted a photo last year in one of our RX3 maintenance tutorials showing the oil/air separator, and the separator was shown upside down (it had been installed that way at the factory).
In a nutshell, here’s the deal: The correct orientation of the oil/air separator is as you see it in the photo below:
There’s a little cap-like closure on the oil/air separator, and that should be on top as you see it in the photos above and below. We’ve noticed people discussing this on the forums and we wanted to give clear guidance on the correct orientation.
The problem crept in with some of the oil/air separators installed upside down from the factory, including the ones on the three prototype RX3s we used for the maintenance tutorials (hence the incorrect photo I used in the maintenance tutorial). As I discovered this weekend, the oil/air separator on my very own RX3 (from the first shipment) was also upside down. Wow. As Bud Abbott would say, “Who’s on first?”
There’s been an enormous amount of confusion on this, so Gerry and I cut a separator open yesterday to find out what’s going on inside. Here’s what it looks like:
That cotton-like thingamajig on the inside is the actual separator. It’s a thick mesh arrangement. The idea is that air comes out of the crankcase heavily laden with atomized oil and fuel vapors (the fuel that sneaks down past the rings goes into vapor form as the engine heats up). When this air exits the crankcase and enters the separator, it flows back to the engine intake (to the air box). It has to go through the separator to get there, and when it does, the atomized oil is captured in that white mesh. From there, it drips down into the drain tube (that’s the clear plastic tube with a plug on the end). The air (stripped of most of the atomized oil) goes on to enter the airbox and get sucked back through the engine.
If you have the oil/air separator reversed (as originally shown in our maintenance tutorial photo), the vapors with atomized oil will go directly to the airbox, with less of the atomized oil being captured by the separator to subsequently go into the drain line.
The bikes are arriving with the oil/air separator in the correct orientation, but some folks think it’s upside down because of that earlier photo we used. They’re turning it to the incorrect orientation. Don’t do that. If your oil/air separator is as shown here, leave it alone. Our apologies for the confusion. I’ll correct the maintenance tutorial photo this week.