When I tighten the non-driveside axle lock nut, it will cause the entire axle and freehub body to “wobble” when it’s rotated. Originally, I thought this was caused by a bent axle, but the problem persisted after replacing it with a new axle from Saris. So after much trial and error, I pinpointed the issue: When the lock nut is only hand tight, the axle barely wobbles. But when the lock nut is securely tightened, the driveside end of the axle, along with the freehub body and cassette, all wobble significantly.

Since the axle is “crooked” in the hub, this problem also manifests itself when the wheel is placed in the bike. Depending on the orientation of the axle, the wheel will be skewed in a different direction than the vertical plane of the bike. With the wheel resting in the rear dropouts, I can use a cone wrench to rotate the axle and see the spacing between the tire and the chainstays, change.

I figured a video would give the folks at Saris a better idea of exactly what was happening. Sometimes phone conversations aren’t the best for describing technical issues. Unfortunately, the camera I have doesn’t have great resolution. And on top of that, more detail is lost due to Google Video’s compression. But if you look closely, you’ll see the wobble during the second part of the video.

I have a feeling they’ll want me to send the whole wheel in, which is what I wanted to avoid. I’ve only had the wheel for a few weeks now, and didn’t want to go back to our remaining PowerTap Pro wheel that Heather and I have to switch between.

Just to leave on a positive note, I will say that the new coded heart rate strap is an incredible improvement over the previous strap! With the older, non-coded strap, I’d have significant periods of no HR reception during most outdoor rides, especially when it was windy out. But with the new coded strap, I haven’t had a single HR drop…not a one! Also, the new CPU has 15 hours of memory (at 1-second recording interval). This is great if you travel and don’t have a laptop to download your rides. You just let them accumulate, then you can download all of them when you get home.