I appear to be having the somewhat common issue of the rear bearings binding when torquing down the rear axle on my '09 EC300.
One post I read indicates the stepped bearing spacer is asymmetric; however, it appears the spacer I have is symmetric, so I'm a little baffled. I looked at the gap between the spacer and the bearings' outer races with the spacer flipped one way, then the other, and it was identical. I also closely inspected the spacer and it really seemed that the location of the inner, raised surface was the same diameter on each side. Maybe it was the cold garage effecting my brain. Or the cold beer.
I can put about 20-30 ft-lb torque on the axle then I start to notice resistance when spinning the rear wheel. At 60 ft-lb the rear still turns, but the friction is quite noticeable.
The post showing the asymmetric spacer was discussing '07/'08 bikes. Did the spacer design change in '09?
Also I'm a bit confused by this design. Generally when you tap or press a bearing in you do it until the outer race seats against a bearing pocket. But in the case of the larger bearing you need to have a gap between its outer race and the spacer - if you go until the outer race is firmly seated, then it's going to be contacting the thinner edge of the washer. Additionally, the outer race might then be pressed in past where the inner race has been seated against the thicker part of the spacer. Is the solution to this to make sure you tap or press the bearing in with a solid-faced cylinder (e.g. the back side, not the open end of a socket) so you also contact the inner race? That also doesn't seem entirely right, since then you'd be putting a side load on the inner race of the inner bearing to provide your stopping point (and transferring a side load to the inner race of the brake-side bearing via the inner spacer tube)
Clearly I'm confused as to how this three-bearing-with-spacer system is supposed to be properly reassembled.  Help! 
One post I read indicates the stepped bearing spacer is asymmetric; however, it appears the spacer I have is symmetric, so I'm a little baffled. I looked at the gap between the spacer and the bearings' outer races with the spacer flipped one way, then the other, and it was identical. I also closely inspected the spacer and it really seemed that the location of the inner, raised surface was the same diameter on each side. Maybe it was the cold garage effecting my brain. Or the cold beer.
I can put about 20-30 ft-lb torque on the axle then I start to notice resistance when spinning the rear wheel. At 60 ft-lb the rear still turns, but the friction is quite noticeable.
The post showing the asymmetric spacer was discussing '07/'08 bikes. Did the spacer design change in '09?
Also I'm a bit confused by this design. Generally when you tap or press a bearing in you do it until the outer race seats against a bearing pocket. But in the case of the larger bearing you need to have a gap between its outer race and the spacer - if you go until the outer race is firmly seated, then it's going to be contacting the thinner edge of the washer. Additionally, the outer race might then be pressed in past where the inner race has been seated against the thicker part of the spacer. Is the solution to this to make sure you tap or press the bearing in with a solid-faced cylinder (e.g. the back side, not the open end of a socket) so you also contact the inner race? That also doesn't seem entirely right, since then you'd be putting a side load on the inner race of the inner bearing to provide your stopping point (and transferring a side load to the inner race of the brake-side bearing via the inner spacer tube)
Clearly I'm confused as to how this three-bearing-with-spacer system is supposed to be properly reassembled.  Help! 
