So what's the deal with the Polar CS600?

[Tom Anhalt]

My understanding of the test was it was done by a person either involved or formally involved with the Australian Institute of Sport cycling program. The first article in the rpevious issue went through the set up process for all the power meters. They did go to great lengths to set up all the un its correctly. So the figures must have some validity.

Show me the data!

Seriously, is there any chance someone can scan and post the complete versions of the 2 articles? The one linked to from the ibike site only shows the ibike section (obviously) on the individual PMs.

The problem I have with them going to "great lengths" to set up the Polar is that they probaby followed the Polar instructions...which IMHO is not much help at all in ensuring an accurate setup. They should've asked ME how to set it up

The main reason I'm speculating a setup issue is that I personally ran a Polar PM setup (S710) vs. a Powertap Pro for over a month on the same bike. The only difference I saw between the readings of the 2 devices was the expected difference due to drivetrain losses (i.e. ~5-10W).

 

[Austin Flyer]

It seems as though one of the critical variables of getting "close" to true power readings from the Polar unit is to ensure that it is set up correctly. And there seems to be speculation that the manual for setting up the system is flawed. So my question is: "How would someone without a powertap set up on the same bike know whether or not the polar unit is giving accurate power readings?" If it's "consistently" reading +-20 watts compared to a calibrated system, would that still be good enough for training and to track progress in fitness.


Since I live in Austin, maybe I should call Lance out for a ride to get his opinion!

 

[Tom Anhalt]

It seems as though one of the critical variables of getting "close" to true power readings from the Polar unit is to ensure that it is set up correctly. And there seems to be speculation that the manual for setting up the system is flawed. So my question is: "How would someone without a powertap set up on the same bike know whether or not the polar unit is giving accurate power readings?" If it's "consistently" reading +-20 watts compared to a calibrated system, would that still be good enough for training and to track progress in fitness.

That's the thing...if it's consistently reading off by that much (and it will more likely be a percentage, rather than a fixed offset) that's a simple case of either the chain weight being entered incorrectly or the chainstay length being mismeasured and entered.

If it's off only in certain gears (typically where the chain is furthest away from the sensor) that's going to be a case of the module not being spaced correctly from the chain.

In either case, without another power meter to run it against, the best you can do is to do a hillclimb and compare it to something like www.analyticcycling.com . When I do that, I'm typically within a handful of watts of the prediction.

IMHO, one of the advantages of the Polar system is that if you just do a couple of simple measurements (i.e. chain weight, chainstay length, and chain to module spacing) there isn't ANYTHING else that should go wrong with the power calculation. It's VERY simple math.

 

[leestevens]

Sure, but for one rider the device underestimated by 6% and 15% for the other, while in another this it underestimated 23-31%. This seems too inaccurate ... although I believe set up is an important issue given everything I have read. Tom's remark regarding measuring chain weight, plus attention to height of the sensor are all relevant to the quality of the data. Nonetheless, out of the box the SRM and PT tracked consistently (sometimes you do get what you pay for I guess).



My understanding from the Polar clan, including the inventor, this was a big limitation of the system ... it did not reliably work on trainer ... this does not appear to have been fixed on the second generation according to this review and other info floating on the net. Personally, I think Polar missed the boat on a few fronts: 1) adequate memory to allow 1 second sampling for more than 2.5 hours; 2) fixing the trainer issue; and it would appear ease of setup is still an issue given this current review.

I know Alan Cote was hoping to test the new Polar system and I would still love to see his findings (especially on a trainer) to make my final judgement ... yet, even if his findings are better you have to be able to reproduce his setup on your own bike. Personally, I guess in the end I have to decide is it worth an extra 800 USD (over the Polar) to get more accurate and consistent data and have the ability to use the system on my trainer. Given that it may cost around the same (or more) to get a trainer/ergometer to track inside training, the PT SL 2.4 is starting to sound like the way to go for me (if I want to get into power-based training. The ergomo is not a consideration for me, as I don't want to give up my FSA K-force integrated compact cranks/BB, plus this review doesn't look that good for the ergomo ... again set up may have been an issue ??

Lastly, I can't speak for Ride magazine, but these things always have to be taken with a grain of salt, as I don't know if any of the companies are bigger advertisers in their magazine (e.g. SRM or Powertap). That's why rigorous independent review by people out in the cycling community are much more valued in the end.

Just to let you know there is a one page ad for the Polar CS 600 during the the review. The Polar hardly got a favourable review. i would post a copy here for people to read but i wouldn't want to infringe any copyright laws.
If you do seriously want to check it out PM me with a home postal address and i will scan and post a copy for you ( i only have the second part, which is the important part). I am considering the Polar and when i saw this test i was a bit unsure, what are other peoples thoughts? I have heard good and bad for all power meters. I want to know more about the Polar. Is the new one any good?

 

[jstock]

iBike - over estimate by 7%. Ergomo - Polar - had some transmission problems and a average over the ride was not possible.

Polar - consistently 23-31% underestimated.

Polar again showed that it was a bit slow to pick up the quick surges, etc and showed a lower overall average power value as a result.

I think it's quite possible that they had a defective surfboard. See my post here.

 

[factory61]

I have seen another comparison (independent) that included the earlier Polar model. The margin of error was not quite as high as this review, but non the less, the Polar products seem to have issues in this area.

IMO, it is better to buy a slightly more expensive/reliable product the first time, rather than purchase an "ecomony" model, find out you're not satisfied, and then purchase the better product.

I believe the Polar is a quality company. However, I have purchased some of their other products (which weren't that inexpensive), had accuracy problems, and then purchased a competitors product to replace the Polar.

Power meters and other such equipment are ment to provide measurements for us to evaluate in order to improve. If the data we are receiving is not accurate, the rest of the process is contaminated from the very beginning.

If you really want the best bang for your buck, buy a used PT SL from a friend or on Ebay, Craigs List, etc. There will be plenty available now that everyone is switching over to 2.4. You will get the accuracy that is necessary to truly evaluate and improve your training and it will only cost you around $750 - $900 and will probably already be laced up on a wheel.

 

[Jore V]

I have seen another comparison (independent) that included the earlier Polar model. The margin of error was not quite as high as this review, but non the less, the Polar products seem to have issues in this area.

IMO, it is better to buy a slightly more expensive/reliable product the first time, rather than purchase an "ecomony" model, find out you're not satisfied, and then purchase the better product.

I believe the Polar is a quality company. However, I have purchased some of their other products (which weren't that inexpensive), had accuracy problems, and then purchased a competitors product to replace the Polar.

Power meters and other such equipment are ment to provide measurements for us to evaluate in order to improve. If the data we are receiving is not accurate, the rest of the process is contaminated from the very beginning.

If you really want the best bang for your buck, buy a used PT SL from a friend or on Ebay, Craigs List, etc. There will be plenty available now that everyone is switching over to 2.4. You will get the accuracy that is necessary to truly evaluate and improve your training and it will only cost you around $750 - $900 and will probably already be laced up on a wheel.

http://www.cyclingforums.com/showthread.php?p=3272967#post3272967