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Re: "Best" power meter - money no object [jkhayc] [ In reply to ]
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I've had stages, 4iii, powertap hubs and currently the favero assioma dual sided pedals. I love the pedals- they are so easy to swap between multiple bikes, and I've had zero issues in 600 plus hours of usage. 4iii was solid too.

That said, if I had a mandate to spend someone else's money and had to buy a new power meter for MSRP, I'd get the Verve Infocrank. Probably the most proven high level of accuracy out there, but you do pay $$ for it.
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Re: "Best" power meter - money no object [rruff] [ In reply to ]
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rruff wrote:
RChung wrote:
Hmmm. Isn't SL+ prior to the G3's? I think they've been reporting at 0.1 inch-lb resolution for a pretty long time.


Yes, circa 2010 or so. If you put it in testing or calibration mode and display torque you get a decimal like 508.3? I only get whole numbers of in-lb.

Sorry, I just saw this. Yup. Torque on my G3 is reported in 0.1 inch-lb resolution.
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Re: "Best" power meter - money no object [RChung] [ In reply to ]
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That sounds like a good reason to get a new hub. 1 in-lb is pretty course sometimes.
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Re: "Best" power meter - money no object [Tom_hampton] [ In reply to ]
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Tom_hampton wrote:
PT hub. That's what I have. It's been totally fit and forget. According to dcr, it's as accurate as anything out there. It's built into a training wheel that I cover for racing.

No muss, no fuss.

How much of a hassle is it putting the cover on and off? I've been very satisfied with the PT Elite+ wheelset I bought second-hand for my road bike, and was thinking about going with a G3/R-460 rear wheel for the tri bike with an AeroJacket for racing.

"They're made of latex, not nitroglycerin"
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Re: "Best" power meter - money no object [RChung] [ In reply to ]
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RChung wrote:
rruff wrote:
RChung wrote:
Hmmm. Isn't SL+ prior to the G3's? I think they've been reporting at 0.1 inch-lb resolution for a pretty long time.


Yes, circa 2010 or so. If you put it in testing or calibration mode and display torque you get a decimal like 508.3? I only get whole numbers of in-lb.


Sorry, I just saw this. Yup. Torque on my G3 is reported in 0.1 inch-lb resolution.

How do you see that? I have a Powertap G3 Track hub and the offset value I get is usually "10" or "11".
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Re: "Best" power meter - money no object [ In reply to ]
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I like the Quarqs and SRMs with someone else's money
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Re: "Best" power meter - money no object [gary p] [ In reply to ]
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Mine is a DIY cover using MonoKote. I leave it on year round. Can't speak to the Aerojacket. But, I think there are tons of other threads that talk about it.
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Re: "Best" power meter - money no object [Tom_hampton] [ In reply to ]
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Tom_hampton wrote:
PT hub. That's what I have. It's been totally fit and forget. According to dcr, it's as accurate as anything out there. It's built into a training wheel that I cover for racing.

No muss, no fuss.

Agreed. It's the most "plug and play" of all the PMs in my experience.

And, since "money is no object", just buy a PT hub for every wheel you ever get for the bike...and you'll still have less total outlay than many of the other PMs mentioned here :-)

http://bikeblather.blogspot.com/
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Re: "Best" power meter - money no object [MTM] [ In reply to ]
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MTM wrote:
RChung wrote:

Sorry, I just saw this. Yup. Torque on my G3 is reported in 0.1 inch-lb resolution.


How do you see that? I have a Powertap G3 Track hub and the offset value I get is usually "10" or "11".

The offset value is different on my head unit than the torque value itself. Didn't PT change the offset value from a number close to 512 to one close to 0?
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Re: "Best" power meter - money no object [RChung] [ In reply to ]
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RChung wrote:
MTM wrote:
RChung wrote:


Sorry, I just saw this. Yup. Torque on my G3 is reported in 0.1 inch-lb resolution.


How do you see that? I have a Powertap G3 Track hub and the offset value I get is usually "10" or "11".


The offset value is different on my head unit than the torque value itself. Didn't PT change the offset value from a number close to 512 to one close to 0?

I think they did, but I'm not that versed in Powertap offset values. I was wondering what one unit in the offset (as showed on my Garmin) corresponds to.
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Re: "Best" power meter - money no object [RChung] [ In reply to ]
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RChung wrote:
MTM wrote:
RChung wrote:


Sorry, I just saw this. Yup. Torque on my G3 is reported in 0.1 inch-lb resolution.


How do you see that? I have a Powertap G3 Track hub and the offset value I get is usually "10" or "11".


The offset value is different on my head unit than the torque value itself. Didn't PT change the offset value from a number close to 512 to one close to 0?

Yes....this was a blog post I did back in 2016.

Mine is usually -12 consistently and I have done a static torque test to verify the G3. Based on what I posted it supposedly be -30 to +30 from a PowerTap blog post.
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Re: "Best" power meter - money no object [RChung] [ In reply to ]
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RChung wrote:
MTM wrote:
RChung wrote:


Sorry, I just saw this. Yup. Torque on my G3 is reported in 0.1 inch-lb resolution.


How do you see that? I have a Powertap G3 Track hub and the offset value I get is usually "10" or "11".


The offset value is different on my head unit than the torque value itself. Didn't PT change the offset value from a number close to 512 to one close to 0?
I think my Garmin uses 1in-lb resolution so perhaps you need the cycleops or a different head unit to get .1 resolution.
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Re: "Best" power meter - money no object [gregf83] [ In reply to ]
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gregf83 wrote:
I think my Garmin uses 1in-lb resolution so perhaps you need the cycleops or a different head unit to get .1 resolution.
That would suck.
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Re: "Best" power meter - money no object [MTM] [ In reply to ]
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MTM wrote:
I think they did, but I'm not that versed in Powertap offset values. I was wondering what one unit in the offset (as showed on my Garmin) corresponds to.
Ah, if I've read the PT site properly (and that's not a 100% sure thing) they switched from displaying torque and offset from inch-pounds to Nm. With the current firmware, one unit is .1 Nm, so an offset value of 10 or 11 means an offset of 1.0 or 1.1 Nm.
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Re: "Best" power meter - money no object [RChung] [ In reply to ]
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RChung wrote:
gregf83 wrote:
I think my Garmin uses 1in-lb resolution so perhaps you need the cycleops or a different head unit to get .1 resolution.

That would suck.
I mis-remembered. The zero offset value is an integer but the torque is displayed to two decimal places. Likely Nm.
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Re: "Best" power meter - money no object [tfleeger] [ In reply to ]
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tfleeger wrote:
Quarq DZero.

I have this meter on all my bikes (cross, road, mtb) for consistency but I've had zero problems with them in a couple of years of use.
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Re: "Best" power meter - money no object [RChung] [ In reply to ]
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RChung wrote:
MTM wrote:

I think they did, but I'm not that versed in Powertap offset values. I was wondering what one unit in the offset (as showed on my Garmin) corresponds to.

Ah, if I've read the PT site properly (and that's not a 100% sure thing) they switched from displaying torque and offset from inch-pounds to Nm. With the current firmware, one unit is .1 Nm, so an offset value of 10 or 11 means an offset of 1.0 or 1.1 Nm.

Thanks, hopefully that's correct as that would be decent resolution. 0.1 Nm is around 1W at 95rpm if my quick math is correct.
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Re: "Best" power meter - money no object [jhammond] [ In reply to ]
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jhammond wrote:
tfleeger wrote:
Quarq DZero.


I have this meter on all my bikes (cross, road, mtb) for consistency but I've had zero problems with them in a couple of years of use.

Be aware that just because you have the same brand/model of powermeter, they are definitely not necessarily reading the same. I've had two Quarqs (different models, though) and we have a handful or so of riders on my team with Quarq DZeros. Haven't rigorously tested them against each other, but from riding with my team in the mountains I am quite certain some of them are several percentages different to others. Of course, for some a 3-4% difference doesn't matter - for me it does.
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Re: "Best" power meter - money no object [AlexS] [ In reply to ]
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I've got a P2M (S Type) with Rotor Q rings and a Powertap G3 - I've never done any specific testing in relation to the oval rings and have never run the P2M with round rings as it came with the ovals second hand.
I have run them at the same time and they tracked pretty much exactly over a 30min ride with varying power between 0 & 500W. The P2M was slightly higher overall (@2%) on average but I would expect that given it is further up the drivetrain and that's also within the accuracy level of the two meters combined.

If the oval rings were inflating the power what kind of variance would you expect to see (a previous poster mentioned 20W) or is it more complicated than that and my N=1 doesn't prove anything either way?

Ps. I bought them both second hand, used them year round in all weather (more so the Powertap) and neither has ever missed a beat so would happily recommend either.
Last edited by: JaRok2300: Mar 8, 19 7:02
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Re: "Best" power meter - money no object [JaRok2300] [ In reply to ]
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It depends on how oval the rings are but years ago one of the oval manufacturers claimed a 3% difference in power by using their rings. So one of the guys on the old Wattage List had an SRM, a PT hub, oval and round chain rings and, most importantly, a high boredom threshold. He did a static torque test on the PT and the SRM with round rings, then collected data from both. Then he swapped to the oval rings, did a static torque test, and repeated the data collection. Compared to the PT, the SRM/oval ring reading was -- drum roll -- about 3% higher than the reading from the SRM/round ring.
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Re: "Best" power meter - money no object [Tom_hampton] [ In reply to ]
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Tom_hampton wrote:
Mine is a DIY cover using MonoKote.

Is there a report on how you did it? Would love to see it.
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Re: "Best" power meter - money no object [MTM] [ In reply to ]
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MTM wrote:
I think they did, but I'm not that versed in Powertap offset values. I was wondering what one unit in the offset (as showed on my Garmin) corresponds to.


Looks like N-m if using Ant+. https://www.powertap.com/...tes-to-offset-values
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Re: "Best" power meter - money no object [rruff] [ In reply to ]
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I followed someone else's report on here for how they did it.

https://forum.slowtwitch.com/...ost=5539564#p5539564

The stuff is very tough. It's surprisingly hard to tear or puncture. So, I just leave it on year round. It's easy to fix if it does get a hole.
Small punctures can be repaired with electrical or clear packing tape. Larger tears can be patched with a piece of monokote.

My rear wheel is a dt swiss r460. I think that's about the shortest profile that will have enough surface area to glue the film too.

A roll of monokote is about $20... And is enough for 1 wheel, plus some leftover for patching, if needed.

Note other heat shrink films such as ultracoat are NOT wide enough to cover a 700c wheel. As far as I know only monokote is wide enough.

There are plenty of colors to choose from and you can get fancy with layers of color if you are so inclined. Mine is basic black.
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Re: "Best" power meter - money no object [rruff] [ In reply to ]
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Re: "Best" power meter - money no object [RChung] [ In reply to ]
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Yup. That too. Only thing I'd say is that a heat gun is about 100 times easier than an iron for large surfaces.
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