Quarq vs. PT with IAero

[doofus]

Looking over the DFPM instructions, the Quarq seems more user-friendly -- just backpedal 4 revolutions and do that occasionally during the ride. The PT looks a bit more trouble -- longer calibration sequence pre-ride (unless you want two head units), and then needing to rezero the torque throughout the ride.

Does anyone use PT with the IAero as a head unit?

How convenient is that combo?

If you don't go through the rezero process mid-ride (seems like a PITA), how much drift? Would that occur anyway with a regular PT head unit?

Thanks

[ludlaw]

I use the iAero head with my PT SL+ and with a HED disc. I occasionally (once a week?) zero it out and generally find very little drift. I also saw the instructions suggesting calibrating it during the ride and am not sure of the reason for that recommendation. Also, I find that doing the calibration via the iAero is really no more or less hassle than using the PT head.

[coachboyd]

I think the Quarq would be the better option just because you can use it with any of your bikes and it's very easy to swap between bikes. You just need a bottom bracket on each bike and then one self-extracting screw takes care of the job.

Granted, it's very easy to swap power tap wheels, but for racing purposes you'd need a training set, race set, and a disc wheel.

[doofus]

I was leaning towards the Quarq for those reasons, Boyd -- plus I've always dug Jonathan's. The original plan was to get the iBike as a head unit, then the Quarq.

The rub is that price -- there's a good deal out there on SRAM 175s, but I use 172.5s -- 300 bucks more.

For the price of that 172.5 Quarq+BB, I can swing a deal on a PT Elite and a set of E-Motions. I could use the iBike with my Cosmics on race days....

Decisions...

[Morocco Mole]

Just make sure you have the "auto Zero" function enabled on the Powertap and you should never need to re-zero it (you need the original head unit to do this though). Every time I have checked it the pcal still reads Zero.

[doofus]

you can do that without the PT head unit mounted?

[coachboyd]

I was leaning towards the Quarq for those reasons, Boyd -- plus I've always dug Jonathan's. The original plan was to get the iBike as a head unit, then the Quarq.

The rub is that price -- there's a good deal out there on SRAM 175s, but I use 172.5s -- 300 bucks more.

For the price of that 172.5 Quarq+BB, I can swing a deal on a PT Elite and a set of E-Motions. I could use the iBike with my Cosmics on race days....

Decisions...

Yeah, but then you don't have race data. I find it handy to analyze a race afterwards (especially with the wind port on the iBike so you can look at when you were drafting or working). I rarely ever set a peak mean maximal power during race day, but it's nice to have the data.

Of course with the iBike + powertap, you can just leave that heavy wheel behind on race day and use just the iBike. That is a huge benefit of using the iBike as a head unit.