I purchased a set of Williams System 30 wheels with a Power Tap SL+ in the rear wheel. I mounted a set of Conti 4000s tires on the wheelset, a Dura Ace 12/25 rear cassette and mounted them on my Cervelo R3.
I have had three rides. The first was a recovery ride at the cycling gym on the rollers 8X5 95/80 cadence 115 to 120 heart rate. The second was a climb up our benchmark climb 3.2 miles in 1475 feet; 7.2% average grade. And the third was a fast paced 30 mile ride with some fast climbing, crosswinds and flatish terrain.
The wheels are much stiffer than my other wheelsets and the ride felt more lively with more road feel. The bumps were more significant although I the roads were generally very smooth. My race XXX lites – 1350 gm, Easton Ascent II - 1475 gm and the Williams 30s 1550 gm. The PowerTap SL+ power meter adds about another 100 gms to bring the total weight increase from the Bontrager Race XXX lites to 300 gm. The net effect is climbing is slower for the same power on steeper hills. However, the 30s are more aero so at some climbing speed the aero advantage will trump the weight. And most of my riding is at faster speeds so I get the aero benefit most of the time. If I want to do a hill climb race, I will use my Race XXX lites.
Descending and braking are excellent. I felt like I could let the bike go (which I did not). My lighter wheelsets seem less stable at higher speed. Not unsafe or speed wobble but they require a lot of attention. The 30s are like a rock descending. The flats were stable and seemed very good. Crosswind performance was good. However, at 170 pounds, I have enough weight so that the gusts do not blow me around as much. Lighter riders may find more aero wheels difficult to control.
I would rate the three rides very acceptable and I am getting use to the feel. It will take a few hundred miles to totally adjust to the ride / handling.
The PowerTap SL+ installed perfectly. It synched up with my Garmin 705 and worked without a hitch. I purchased the SL+ without the HR monitor or computer since I had that with my Garmin 705. Also, there are less expensive versions (one more expensive) than the on I purchased. I wanted the lighter version with larger bearings. And I could get it in all black. If I want to swap the PowerTap to my TT bike all I have to do is swap the wheels and the 705 and I have power. The PowerTap provides speed, virtual cadence and power. If you have a Garmin Speed cadence / speed sensor, the Garmin will use the cadence from the Garmin unit and the speed from the PowerTap.
It is pretty cool getting a power readout along with HR and speed. I am not going to get into my power numbers and etc. but I will say that I am surprised by the lag between breathing and HR to power increases. My power can increase a lot and my breathing and HR slowly catch up. I suggest that as anyone commences a climb, they start deep breathing right away. Do not wait until your body decides to increase breathing. It is too late. Likewise, after a climb and if there is a flat or false flat and the HR and breathing are up, the power may be down even though you feel like you are putting out a lot of effort. Effectively, you have overcooked the climb. In group rides and races, this is necessary but knowing what is happening may allow one to mitigate its effects to an extent.
Here are a couple of pics