# powertap g3 vs gs



## mmbuckwa (Dec 27, 2008)

Between the powertap G3 and GS is one a clear winner? The GS is straight pull, 24 spoke and the G3 has J bend with more spoke options. The GS looks more appealing due to its DT swiss internals but is there anything I'm missing about the G3 that would make it the better choice if 24 spoke is enough for my weight?


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## MMsRepBike (Apr 1, 2014)

G3 is cheaper and there's lots of them out there.

GS is better built, more solid. DT Swiss vs. Novatec.

I'd take either.


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## Srode (Aug 19, 2012)

Can't speak to the GS but I have a G3 with over 10,000 miles on it and zero problems with it - just put a battery in it once in a while.


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## mmbuckwa (Dec 27, 2008)

Thanks for the feedback. Does anyone own one of the powertap amp carbon wheelsets? I am interested in their durability as an every day training wheel set for a 175 pound rider.


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## tvad (Aug 31, 2003)

MMsRepBike said:


> *G3 is cheaper* and there's lots of them out there.
> 
> GS is better built, more solid. DT Swiss vs. Novatec.
> 
> I'd take either.


G3 and GS same price at Wheelbuilder.com $599.99.


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## TmB123 (Feb 8, 2013)

Just curious - with all of the pedal, crank and spider based PM options around these days, what advantages are there for going for a wheel based PM? 
Just seems to limiting your options for use.


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## mmbuckwa (Dec 27, 2008)

I have two bikes, one with a bb30 and the other with a gxp crankset. I figured swapping rear wheels would be the simplest and cheapest way to measure power on both bikes and also give the most consistent readings. For around a $1000, is there a better choice or are the powertap wheelsets prone to problems not inherent in other designs?


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## tvad (Aug 31, 2003)

TmB123 said:


> Just curious - with all of the pedal, crank and spider based PM options around these days, what advantages are there for going for a wheel based PM?
> Just seems to limiting your options for use.


How does a wheel limit options for use? Take it off one bike and put it on another bike. Adjust brakes as needed.

A wheel-based power meter is less expensive than a dual (L/R) crank based power meter, and you're not limited to a specific pedal system in the case of pedal-based power meters. 

Also, a wheel-based power meter does not give a handicapped power reading in the case of one leg being weaker than the other (a disadvantage of single side power meters). I have a L/R crank power meter, and if I don't monitor my power balance, my left leg will often produce 10-20% more power than my right leg. 

That's not an issue with a hub based power meter.


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## TmB123 (Feb 8, 2013)

tvad said:


> How does a wheel limit options for use? Take it off one bike and put it on another bike. Adjust brakes as needed.
> 
> A wheel-based power meter is less expensive than a dual (L/R) crank based power meter, and you're not limited to a specific pedal system in the case of pedal-based power meters.
> .


there are pro's and cons for both, but what I meant was that you are always stuck with that one wheel to use. The PT hub is probably one of the more reliable and cheapest options out there, but I would rather swap pedals between bikes than wheels, not from a speed/ ease perspective, but I prefer to have different wheel options - training, racing, aero, light weight etc. No matter which way you go (wheels, pedals etc) you are locking yourself into a "system", but me personally would prefer something other than a wheel.


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## TmB123 (Feb 8, 2013)

mmbuckwa said:


> I have two bikes, one with a bb30 and the other with a gxp crankset. I figured swapping rear wheels would be the simplest and cheapest way to measure power on both bikes and also give the most consistent readings. For around a $1000, is there a better choice or are the powertap wheelsets prone to problems not inherent in designs?


Yes it would be, as long as you don't want to use different wheelsets then that would be the best option. I guess I dont know many people, especially those with PM's that don't have at least a couple of sets of wheels lying around for various use these days.


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## tvad (Aug 31, 2003)

TmB123 said:


> I would rather swap pedals between bikes than wheels, not from a speed/ ease perspective, but I prefer to have different wheel options - training, racing, aero, light weight etc. No matter which way you go (wheels, pedals etc) you are locking yourself into a "system", but me personally would prefer something other than a wheel.


That's a valid argument for sure.

BTW, if you use Shimano cranks...I'm talking about the current cranksets...they are very easy to uninstall and reinstall. Takes about 10 minutes. So, a crank based system like Pioneer's is pretty easily swapped between bikes. Not as easy as pedals...but still easy.


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## TmB123 (Feb 8, 2013)

A Shimano crankset swap would probably be quicker than a Garmin Vector swap with the pods and calibration etc, glad to see newer brands aren't as fussy.
I've been running a DA 9000 Stages crank for the last couple of years which has served me well but the dual l/r data does have me intrigued somewhat.


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## tvad (Aug 31, 2003)

TmB123 said:


> I've been running a DA 9000 Stages crank for the last couple of years which has served me well but the dual l/r data does have me intrigued somewhat.


I have a DA9000 groupset with Pioneer L/R PM, and had been considering a new Pioneer left crank PM for my second bike, since the price dropped on the Pioneer left crank unit. Then, I did a few rides and paid no attention to the power readings during the ride. When I looked at the data and realized my left/right balance was out of whack (and I usually ride with a good L/R balance when paying attention during the ride), I realized a left only PM was not going to be advantageous for me.


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## Srode (Aug 19, 2012)

tvad said:


> I have a DA9000 groupset with Pioneer L/R PM, and had been considering a new Pioneer left crank PM for my second bike, since the price dropped on the Pioneer left crank unit. Then, I did a few rides and paid no attention to the power readings during the ride. When I looked at the data and realized my left/right balance was out of whack (and I usually ride with a good L/R balance when paying attention during the ride), I realized a left only PM was not going to be advantageous for me.


Same experience here - and one of the reasons to have a true L/R reading crank based PM to me. I'm working on training muscle memory to improve the normal L/R balance and making some progress through focusing on the left side while riding, both road and on the trainer. 

My frames all use Shimano hollowtech / 24mm spindle cranks so moving a crank based PM from bike to bike isn't an issue.


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## tvad (Aug 31, 2003)

Srode said:


> I'm working on training muscle memory to improve the normal L/R balance and making some progress through focusing on the left side while riding, both road and on the trainer.
> 
> My frames all use Shimano hollowtech / 24mm spindle cranks so moving a crank based PM from bike to bike isn't an issue.


Ditto. I have a nagging right hip issue that causes my left leg to compensate. The L/R power meter is helping me to balance the work load. I'll have to say, looking at the numbers from the few rides I recently did when I didn't pay attention to power balance was revealing...and a little shocking, as I thought I had re-trained my legs, but the numbers showed otherwise.


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## Srode (Aug 19, 2012)

tvad said:


> Ditto. I have a nagging right hip issue that causes my left leg to compensate. The L/R power meter is helping me to balance the work load. I'll have to say, looking at the numbers from the few rides I recently did when I didn't pay attention to power balance was revealing...and a little shocking, as I thought I had re-trained my legs, but the numbers showed otherwise.


I've been working on this since early November with the Pioneer meter - it's slowly showing up - I've got many more months of work before it's my natural stroke.


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## TmB123 (Feb 8, 2013)

Curious to know that when the numbers are telling you that one leg is weaker than the other (when you weren't paying attention to the numbers but could still see the data afterwards) was your overall avg power or avg speed down, or does the other leg compensate for the difference?


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## tvad (Aug 31, 2003)

TmB123 said:


> Curious to know that when the numbers are telling you that one leg is weaker than the other (when you weren't paying attention to the numbers but could still see the data afterwards) was your overall avg power or avg speed down, or does the other leg compensate for the difference?


My average speed was not down.

I rode today, and my average balance was 51/49. Not bad. I set a marginally faster average time, but I've only been back on the bike for 10 days after being off for nearly six weeks due to illness.


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## deviousalex (Aug 18, 2010)

The one thing that I really dislike about the PowerTap (I've had 2 G3s) is that their bearings are complete crap. The ones on my rear wheel have 5-6k miles and are super rough. If I spin the rear wheel of my bike while holding the saddle I can feel the grittiness. PowerTap replaced these bearings when they fixed the PM for me and they started feeling a little gritty after about 1k DRY miles.

I'm thinking of taking it to my LBS and having them press in some Phil Wood bearings for me. PowerTap claims they are the only ones that can press in new bearings but I'm not going to send my PM back to them just to have them press in some crap again.


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## Srode (Aug 19, 2012)

TmB123 said:


> Curious to know that when the numbers are telling you that one leg is weaker than the other (when you weren't paying attention to the numbers but could still see the data afterwards) was your overall avg power or avg speed down, or does the other leg compensate for the difference?


on harder efforts the balance for me get's closer than casual riding, maybe 5% difference vs 10 or 20% when I'm not paying attention. My average speed hasn't changed really because I mostly do group or trainer rides and the trainer rides are intervals. I'm hoping getting the balance closer to 50/50 will show up on long rides more so than hard efforts, however once the left leg get's stronger (will take more than a few months) it should show up on hard efforts too. Time will tell, maybe a year from now I will have a better idea of what the benefit is actually vs just on paper although it will be hard to say what is L/R balance and what is smoother more effective pedal stroke since I'm working on that simultaneously.


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## MMsRepBike (Apr 1, 2014)

deviousalex said:


> PowerTap claims they are the only ones that can press in new bearings but I'm not going to send my PM back to them just to have them press in some crap again.


You have that partly wrong. Obviously anyone can install bearings that has the proper tools and bearings.

What you missed though is that if you replace the bearings the unit is worthless until it gets sent in for calibration.

No, you cannot calibrate a power meter by yourself, it's impossible. You can zero offset it but to calibrate it it has to be sent in. 

So go ahead and replace the bearings yourself if you want but you still have to send it to them or it's trash.


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## tvad (Aug 31, 2003)

deviousalex said:


> The one thing that I really dislike about the PowerTap (I've had 2 G3s) is that their bearings are complete crap.not going to send my PM back to them just to have them press in some crap again.


Good reason for those considering a Powertap hub to buy the GS, which has DT Swiss internals and now costs the same as the G3.


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## changingleaf (Aug 20, 2009)

If your bearings are wearing that fast it's likely because the axle spacing is too short so when the skewer is tightened it preloads the bearings too much. I had that problem on an old powertap, but my G3 is the opposite. The axle spacing must be slightly longer than the hub spacing because I have very slight wheel play in the rear with the skewer cranked down. I don't mind though because the play is minimal and the bearings aren't preloaded, so they still don't show any sign of wear after about 8000 miles.

I've seen this issue on other hub brands as well and it's very disappointing. It might be solvable with another axle.


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## deviousalex (Aug 18, 2010)

changingleaf said:


> If your bearings are wearing that fast it's likely because the axle spacing is too short so when the skewer is tightened it preloads the bearings too much. I had that problem on an old powertap, but my G3 is the opposite. The axle spacing must be slightly longer than the hub spacing because I have very slight wheel play in the rear with the skewer cranked down. I don't mind though because the play is minimal and the bearings aren't preloaded, so they still don't show any sign of wear after about 8000 miles.
> 
> I've seen this issue on other hub brands as well and it's very disappointing. It might be solvable with another axle.


I highly doubt PowerTap will warranty my hub based on this suspicion. I've had Novatec (who makes the G3 hub shell) hub bearings get gritty in less than 500 miles. I pressed some decent quality ones in there and problem solved.


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## Pirx (Aug 9, 2009)

For what it's worth, I've got 15k miles on my rear Powertap (G3, Zipp 404 rim), and it spins just like new. It has seen some rain (anywhere from constant drizzle to massive rainstorms), but overall I try to stay off the bike when the roads are wet, so total miles in the rain are probably on the low side.


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## Clipped_in (May 5, 2011)

TmB123 said:


> Just curious - with all of the pedal, crank and spider based PM options around these days, what advantages are there for going for a wheel based PM?


As has been eluded to in other posts, hub based PM's have been around a relative long time. They are a proven, reliable, and economic system. A lot of the others can be quite finicky. In my experience, the Powertap G3 simply works and does what it's supposed to do--no questions asked.


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## Pirx (Aug 9, 2009)

Clipped_in said:


> As has been *eluded* to in other posts, hub based PM's have been around a relative long time.


The word you want is "*alluded*". You're welcome.


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## deviousalex (Aug 18, 2010)

Pirx said:


> For what it's worth, I've got 15k miles on my rear Powertap (G3, Zipp 404 rim), and it spins just like new. It has seen some rain (anywhere from constant drizzle to massive rainstorms), but overall I try to stay off the bike when the roads are wet, so total miles in the rain are probably on the low side.


There could be bad QC on the bearings and you got a good pair.


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