Lets see your PowerTap!
This is the place to share your experiences with PowerTap. Please feel free to post pictures, ask questions about anything PowerTap related or power related for that matter. We will do our best to answer your questions, give feedback and share information whenever possible. We are experts in our field and are happy to share information with our loyal users when we can.
Wired Powertap. Bombproof. All day.
Half Disc
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Have had a HED Jet 9 with a powertap for about a year and a half now, generation 2. Wife and I share it. Has worked without problems so far, even survived a car crash and torrential rains. We use it for training, road racing, and put a wheel cover on it for time trials/multisport events.
We use the “little yellow computer” as a head unit which I dig because it is cheap, and aero shaped 
Have raised FTP from ~250 to ~270 in the last year with it. Pacing time trial efforts with it is a massive advantage. I’ve definitely improved my placing due to that, especially in events with a lot of wind and climbs which can make pacing optimally tricky to do by feel.
Me in a road race:
Wife in a TT with the wheelcover on
If you need a power meter that is going to be used on many bikes, a HED Jet wheel + wheel cover will work well for all situations. It is a nice setup.
wow - you’ve been back for a while and I missed it. welcome.
Okay, I’d like to know how much variability is too much.
I have an older ant+ model and a joule 2.0 head unit. I notice the readings fluctuate on the powertap way more than say on my power measuring trainer. Others have reported the trainer as being fairly precise, at least the way I’m using it. I’ve done the stomp test, and all looked well, as far as I can tell. I was imagining centrifugal force causing a bad connection, but it’s also possible this is how much the numbers are supposed to vary. I have the head unit set on 6s averaging. I never looked into whether it stores the data filtered with some kind of 6 second window, or whether it displays it that way.
So what are the tests an advanced user can do to diagnose his PM?
Thanks
why does my powertap have twice the variability in readings as my quarq?
ie yesterday on trainer ride, a 6min segment, PT(min,max,avg) 277,375,325 Quarq 320,370,342
the powertap seems to jump around way too much even on 3sec avg, ie 270,310,285,305,268 whereas quarq is 305,310,306,308 for same segment of riding. both on 3 sec avg the numbers jump every sec or so
hanging a known static weight from cranks, it seems to be within margin of error and zero offset is 502, so that seems good, just dont get the jumping around so much. looks like a seismegraph in wko+
2011 Zipp 404 w/SL+
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No pictures.
First - I am very pleased with my powertap(s). I have owned 3 hubs: SL+ 24h (sold), SL+ 20h, Elite+ 20h.
I have owned an LYC, and 2x Joule 2.0s.
I am quite happy with my decision to switch from SRM to a powertap and have only had a few issues.
1> The last time I checked the LYC suffers from time dilation - reported here: http://forum.slowtwitch.com/gforum.cgi?post=2969032 As far as I know, still not resolved.
2a> My original Joule 2.0 had the interval button go bad after about 3 months of use, the second Joule 2.0 is now almost 2 years old and the mode button/joystick are starting to become a little finicky. IMO - those buttons should have a lot longer life then that!
2b> I semi-regularly experience data corruption on my Joule 2.0, that requires me to run chkdsk on it. I have an athlete (Mac user), that has this occur more often then not and is constantly calling for support to fix it.
3> At both Kona 2011 and Kona 2012, my Joule 2.0 experienced cut outs around Mauna Kea resort, just prior to the turn off the Queen K. In 2011, I figured it was due to low batteries, but in 2012 I put fresh batteries in - still an issue. Maybe everybody using wireless got nailed there though…literally the only place I’ve ever had issues; not even in my basement 5 feet away from my TV, stereo, computer, and two giant fans.
That’s the only complaints I’ve got about ~3 years of powertap usage. If I hadn’t just acquired a Garmin 910XT, I’d be buying a Joule GPS - maybe in a few months.
why does my powertap have twice the variability in readings as my quarq?
ie yesterday on trainer ride, a 6min segment, PT(min,max,avg) 277,375,325 Quarq 320,370,342
the powertap seems to jump around way too much even on 3sec avg, ie 270,310,285,305,268 whereas quarq is 305,310,306,308 for same segment of riding. both on 3 sec avg the numbers jump every sec or so
hanging a known static weight from cranks, it seems to be within margin of error and zero offset is 502, so that seems good, just dont get the jumping around so much. looks like a seismegraph in wko+
My guess is that it is because the Quarq is sampling over one pedal revolution whereas the PowerTap samples over some amount of complete wheel revolutions. So the PowerTap will sometime sample over only or mostly the ‘power phase’ of your pedal revolution and other times only or mostly over the dead spot, hence varying more. Quarq (and SRM, and probably also Power2max) will always have both the power phase(s) and the dead spot(s) in each reading.
Glad you’re back Jack!
I love my PT. I bought it used from ST classifieds several years ago and it’s still going strong. I have a 2.4sl wireless on a Mavic Open Pro. I train on it and slap on a wheel cover for races. I have had several false starts into purchasing a crank based PM but have stuck with my PT. In a thread from yesterday, which I can’t find right at the moment to link, another powertap rep/person started talking about an ‘upgrade’ program to the new hubs but didn’t post details. Could you confirm that such a program exists and what the details may be??
Thanks,
Jamie
Welcome back. I was doing some research on new tires/tubes a while back and was wishing you were still on slowtwitch to sum up everything I needed to go out and find on my own.
I love my PT. I bought it used from ST classifieds several years ago and it’s still going strong. I have a 2.4sl wireless on a Mavic Open Pro. I train on it and slap on a wheel cover for races. I have had several false starts into purchasing a crank based PM but have stuck with my PT. In a thread from yesterday, which I can’t find right at the moment to link, another powertap rep/person started talking about an ‘upgrade’ program to the new hubs but didn’t post details. Could you confirm that such a program exists and what the details may be??
Thanks,
Jamie
Thread is this one and I am also very curious. Seems like a great program.
Same here. I’m ready for an upgrade too.
Couple questions.
I have a set of TTR3 wheels with a cover on the rear that I use for my everything wheels, at least until I can afford a better front. I got a used SL+ powertap that I want to lace into the rear wheel. I know that I need the dimensions for the wheel and hub so I know what size spokes to order - where can I find that info? I emailed Felt, but no response yet. I have a LYC, how can I ensure that the PT is fully functional before I spend the $$ on the spokes?
Thanks.
Any consideration around supporting wired models going fwd? Will there be continued manufacture of wired harnesses, etc.?
I understand the business case for not supporting them but considering how long the wired PTs can last it seems that it wouldn’t be a bad idea to support them somehow.
Fwiw, I have three wired PTs with assorted spare parts, harness, etc. and the fact is that I can source a working used PT for less then the cost of an upgraded unit even with a loyalty program. At some point the cost/benefit of owning a wired unit goes south but until then I’m using 'em.
What are the upgrade options from wired to ant+? What is the cost to replace the insides of the hub with a wireless hookup? What is this loyalty program I hear of? I have two wired PTs and don’t want to go to a crank based system.
Thanks.
I’d also be interested if there is an upgrade program for an older pro hub with the yellow cover, even if I needed to switch the whole hub out.
That thing keeps going and going like the Energizer bunny.
jaretj
Love my SL, but why dies it come apart after unpacking from bike box? Happened last two trips. And the guy at whos place i was staying - a cycle tour host - said its not uncommon. Packed tight in box, skewers out, good amount of pressure from the bike box and when i open it up the the entire cassette and ‘freehub?’ come right off. All snaps back together no problem, but still…