Commuting, with power

Is Power2Max a user-serviceable battery? I forget which one needs to be returned for battery servicing. I'm very happy with my Stages but I actually ordered a Power2Max originally, only cancelling it when they confirmed that it would be nearly a month before I got it.

Yep, P2Max is a good fit and forget solution. User-replaceable batteries, and seems (had mine a couple of years) to be weatherproof. Other benefits are that it only takes 5 mins to swap between bikes, and it doesn't constrain your choice of wheels. I've used mine on the commute, TT-ing with a disc wheel, and if I wanted to I could put it on the cross bike.

i like my stages.

Yes plus 1 on the Power2max. Just fit and forget. The battery's are watch type Renato make them you can order from Amazon. Easy to change just don't lose the screws.

When I vaguely looked into this (and let's be honest I'm not good enough to even come close to needing a powermeter :oops: ), I was quite taken by the Stages ones, just looked so simple to fit / use etc

http://www.sigmasport.co.uk/item/Stages ... YG?wmp=955

Personally I think the left leg thing is a red herring relative to the simplicity of the Stages. By all accounts (and my experience) they're now totally weatherproof. I run a standard double on my Foil and a compact on my Volagi and turbo bike - if I had a CX that would be a third different set of chainrings. Unless you have a specific reason to know your power balance, I don't think it's a big deal versus the benefits of the Stages.

iPete wrote:

I'm not bothered about LR either. What puts me off stages is being first gen and the number of users reporting niggles.
Saying that, it seems incredibly simple, shouldn't add much weight and replaces(?) the need for a cadence sensor.

However, the price point still feels too high.

105 5700 Chainset and Stages = £680
Ultgra 6700 Chainset and Stages = £825

Reading around, many of the people who had issues at first are now happy. As for weight, my 105 Stages is only 13g (yes, 13) heavier than the Ultegra 6700 crank. It is incredibly simple, uses BT, and I think is more flexible than the P2C.

I would buy the 105 Stages and an Ultegra Chainset (that's what I did - I could sell the SL-K that it replaces) - about £720 in total. You can't tell that the Stages doesn't match - the colour is the same.

iPete wrote:

Hmmm, been reading the DC Rainmaker reviews, very tempted now.

It does however feel odd paying £600 for something that weighs less than 20g! An entire wheel or chainset feel a bit more tangible.

Indeed! You can get an entire Ultegra 6800 Groupset with the money and get change.....however since you've started this thread, I'm tempted by the Stages, especially I already have an ultegra crankset.

http://www.brimbrothers.com/

Talius wrote:

http://www.sigmasport.co.uk/item/Stages-Cycling/Shimano-Ultegra-6800-Power-Meter-Crank-Left-Arm-Only/2OYG?wmp=955

"STAGES CYCLING SHIMANO ULTEGRA 6800 POWER METER CRANK - LEFT ARM ONLY"

But I want it to measure my leg power.

barry_kellett99 wrote:

meanredspider wrote:

Personally I think the left leg thing is a red herring relative to the simplicity of the Stages. By all accounts (and my experience) they're now totally weatherproof. I run a standard double on my Foil and a compact on my Volagi and turbo bike - if I had a CX that would be a third different set of chainrings. Unless you have a specific reason to know your power balance, I don't think it's a big deal versus the benefits of the Stages.

In what way is it a "red herring"?
It's got nothing to do with power balance.

Do enlighten. I was under the impression that there wasn't a great deal of benefit knowing the difference between right and left leg power.

spasypaddy wrote:

there is a benefit.

basically the stages is guessing your power from knowing what your left leg is doing.

but what if your right leg is 60% stronger. stages is giving you a reading of:
200 which is 100 watts for each leg. but your real reading should be 260 or something

however at our level of performance IMO all we should really care about is consistent readings and that is why the stages is more than sufficient.

and this is from a stages user

But what are you going to do with the information (that makes it a benefit)?

For starters, everybody on "Road Fitness" or whatever the BR sub-forum is called, will tell you that power is to do with your cardiovascular system and very little to do with leg strength. If your left leg is a little different (figures of 2-4% typically get quoted) it really doesn't matter - it won't alter what you do as a result. Now, like my son, your left leg is substantially different from your right (through surgery and nerve damage in his case) then maybe there's an argument to measure both but, as you say, for most of us consistency is key.

I've red a lot about these PMs and I've yet to find anybody who can actually explain how power balance can help. Now, if the left leg thing isn't about power balance, then I'm lost.

And all this from someone who tried buying two different L&R PM systems before I gave up and ended up with a Stages.

dhope wrote:

Do enlighten. I was under the impression that there wasn't a great deal of benefit knowing the difference between right and left leg power.

Stages can't give you that information. Neither can the majority of powermeters on the market. Some will say they can, but they are also making assumptions rather than taking actual readings.

The point I was making is that, as paddy has pointed out, Stages is guessing your right leg output. Whether that is important to you or not is not really the issue. The issue is that some of the power2max sensors are in the same price bracket and measure actual power from both legs.

There have been a few studies that also suggest that your legs fatigue differently over long durations of effort, meaning that potentially on a long ride, stages could be guessing it accurately at the start of a ride, but as the ride goes on it could become further and further out.

If all you need to see is a number in front of you, thats grand. Its acceptable to me for XC racing because it is notoriously hard to estimate TSS using just heart rate alone, and due to the short punchy nature of the riding, I am prepared to accept the possible innacuracy, as I agree with you, it will be relatively small and I feel even less so when cranking out 30-60 second bursts followed by coasting

The point I made above was that I can't understand why anyone would go down the stages route unless you already had a standard crank (length/manufacturer/model) on all your bikes.

meanredspider wrote:

For starters, everybody on "Road Fitness" or whatever the BR sub-forum is called, will tell you that power is to do with your cardiovascular system and very little to do with leg strength.

For something like time trialling this is a fairly accurate assertion. For anything involving anaerobic power (eg track sprints, sprints at the end of road races or at the start of cross races) your cardiovascular system may not be that relevant at all.

rower63 wrote:

But if you’re ever comparing against others, or you have a TT course gradient-map and all the cycling-related physics equations and you want to simulate an elapsed time for a given average power, or if you have a package that can do that, then true power matters.

One very important example of this is using something like Golden Cheetah to determine your CdA (aerodynamic drag), which is a key tool for TTers working to refine their equipment/position. To have even a chance of getting meaningful numbers, your power meter needs to be accurate and calibrated.

iPete wrote:

I could probably build a wheel that is strong enough for all year riding AND the odd race/TT, something like a 24h Archetype with CX Ray (or other lighter rim?!). I'd then get money back selling my 2 modest wheelsets but I'd miss the whizz of Hope hubs.

Paging ugo to the thread..

If you want a 24 with aero spokes, I would use a less weight weenie spoke, that actually does the job. I can get hold of DT Aero Comp (surprisingly only in black... ) the cross section is similar to CX Ray (1.1 mm Vs 0.9) but it builds a significantly stiffer wheel. They are also a bit cheaper.
Would probably still keep the Hope for those dreadful days (are they not due new rims by now? :shock: ) as the Powertap is a Novatec thingy after all, not the most durable hub/freehub mechanism and you are not exactly easy on your wheels