CH Aero/Wheelbuilder disk cover report (pretty long)

As some of you may know, I recently got a new rear wheel from Rich at www.wheelbuilder.com. I had purchased a PowerTap SL hub off ebay pretty cheap. Although it was new, there were two drawbacks: it was only 24-holes and it was a Campy drive. Replacing the free hub was possible, but was going to cost me $60 for the new body. The 24-hole drilling limited my selection of rims, especially since I need 650 wheels.

Rich at Wheelbuilder came very highly recommended by the guys at Velocity rims (who called him one of the top builders in the country). Not only were his prices for building the wheel reasonable, but since the hub was new and he built quite a few wheels with them, he offered to swap it for a 28-hole Shimano hub for no charge. Outstanding customer service!

I got the wheel last week and have taken a few rides on it. Having the power is great and well definitely aid my preparation for IMLP next year.

Tonight, I decided to take the disk wheel cover I bought along with the wheel out for a semi-scientific test ride. According to the scale in my kitchen (which may be of questionable accuracy), the cover weighs 380 grams. It attaches to the wheel using 8 plastic screws around the outside edge. Rich cut the cover to fit my rim and the PT. He can trim the cover to fit pretty much any rim/hub combo you tell him to. I rode for 15 minutes to warm-up, stretched, and then rode a 4.85 mile loop without the cover. I went home, put on the cover, and then rode the same stretch again. The cover attaches easily, although you do have to remove your cassette to put it on.

Here are the numbers:
1st run: Avg. power: 201 watts Avg. cadence: 95 Time: 13:25 Avg. speed: 21.6
2nd run: Avg. power: 186 watts Avg. cadence: 95 Time: 13:20 Avg. speed: 21.8

I think because my legs are still a bit worn from yesterday's 2 1/2-hour ride, I couldn't maintain quite the same power for the second loop. In fact, my average power was nearly 8% lower on the second run. Despite that, my time was 5 seconds faster on the second loop.

While it's a stretch to draw conclusions from a single trial, this anectdotal test shows a pretty significant gain using the cover. I plan on recreating this over a slightly longer course. I'll keep everyone posted. Pics follow...


Edited by dgunthert 2005-09-20 8:34 PM












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disk4.jpg (32KB - 659 downloads)
disk3.jpg (16KB - 12 downloads)
disk1.jpg (27KB - 649 downloads)
disk2.jpg (40KB - 13 downloads)