"ibike" powerMeter

[Dr. Seuss]

nice comparison document BM!

 

 

 

[BikeMax]

 

nice comparison document BM!

 

 

 

 

Thanks, credit must go to Adrian at Bicycle Power Trading as he spent many hours on it.

 

[Brakkies Sport Fotos]

golefty, thanks, but I'm not good enough to splash around killarney on a powertap.

 

 

 

I'm looking at a iBike, (and just got a pm were I can get 'n brand new - sealed in a box - for R4k.

 

 

 

So, I'm only concentrating on to find out if the ibike pm will be good enough and give enough "correct" data to analize and to see how to improve.

[GoLefty!!]

Popeye, I'm not advocating you purchase PT at all.

 

n my view the I-bike would be good enough.

After looking at the "comparison" doc downloaded from the given url I have to say that I was pretty amused at how blatantly the "Comparison" is a marketing exercise  .......

 

I'd suggest you do some of your own research on the web to see what others are saying about either.

There are folk here with a vested interest in a certain product and it's highly unlikley that you would get a balanced opinion out of them.

 

I would even consider the Polar HRM and powermeter bundle if it's only for road use and you merely want to monitor your progress over time....

 

Jet aircraft use Ibike principals to tell them how fast they're flying, how high, how much drag, how much thrust etc, etc so the principal is not new and Newtonian physics have been proven to be ideal for estimating performance of moving bodies in Planet Earth.

 

Starin gauges can be more accurate, more of the time but at what price does that accuracy come? (not just the cash you hand over)

 

What you want to something simple to use, and cheap.

 

Alsoif you're going to buy PT you shuld get the Training Peaks software as well since the PT training softwares is pooh.

 

Training Peaks cost's $99.00 so add that into the basket.

[BikeMax]

 

Bikemax.

 

So ibike "estimate" power but powertap really "measure" it?

 

If you can estimate' date=' what % difference will it make in using that data to train correctly?[/quote']

The ibike does not estimate anything. It measures wind speed, rolling resistance and grade, and it calculates power.

The PT does not measure power, it measures strain, and also calculates the corresponding power.

The ibike is as accurate as the PT when the conditions are the same as when it was callibrated, but will be less accurate when the conditions change, such as when you sit up as opposed to being in the drops. 

 

Lets put it like this then - the Ibike is an indirect measure of power as opposed to a direct measure (such as SRM, PT, Ergomo)

 

In terms of Ibike being as accurate as PT when the calibration conditions are the same - the calibration conditions are a fundamental variable when riding (weight, draft, smotthness of road etc) and so this statement is largely meaningless when making a comparison of the two.

 

[Windbreaker]

 

Very few people that have shelled out a lot of bucks for one will tell you that they made the wrong decision so their advice is often somewhat biased.

 

 

So I'm one of the few. My first PM was a Polar Power sensor, and I bought it based on a price consideration.

Although it was difficult to set up the main downfall was that it was useless on an indoor trainer - it has issues with trainer vibrations. In the winter I do a lot of training indoors so it became a serious issue for me.

 

The next biggest problem is that it only records data at 5s intervals. I compared the Polar data with that of my newly acquired PT for a couple of weeks and the comparative average & NP data for rides was fairly consistent. So accuracy of data is not a big Polar flaw in my opinion.

 

I understand the principles of operation of all the PM's and am very acquainted with the failings of the Polar. This makes me all the more suspicious of the iBike although I admit that I have never tried it myself.

 

If I was price conscious (again) and happy enough to accept that I could live with a PM that could not operate on an indoor trainer then I would probably opt for the Polar again as opposed to the IBike.  The variables that the Polar technique has to deal with are far fewer than the iBike so IMO opinion it will be more accurate than the iBike.

 

Yes the Polar is an ugly SOB but I am past the stage of placing "bling" above functionality in terms of attractiveness.

 

[BikeMax]

 

 

Popeye' date=' I'm not advocating you purchase PT at all.

 

n my view the I-bike would be good enough.

After looking at the "comparison" doc downloaded from the given url I have to say that I was pretty amused at how blatantly the "Comparison" is a marketing exercise  .......

 

I'd suggest you do some of your own research on the web to see what others are saying about either.

There are folk here with a vested interest in a certain product and it's highly unlikley that you would get a balanced opinion out of them.

 

I would even consider the Polar HRM and powermeter bundle if it's only for road use and you merely want to monitor your progress over time....

 

Jet aircraft use Ibike principals to tell them how fast they're flying, how high, how much drag, how much thrust etc, etc so the principal is not new and Newtonian physics have been proven to be ideal for estimating performance of moving bodies in Planet Earth.

 

Starin gauges can be more accurate, more of the time but at what price does that accuracy come? (not just the cash you hand over)

 

What you want to something simple to use, and cheap.

 

Alsoif you're going to buy PT you shuld get the Training Peaks software as well since the PT training softwares is pooh.

 

Training Peaks cost's $99.00 so add that into the basket.

[/quote']

 

Go Lefty

 

I am sorry that you feel that the comparison document is a "marketing exercise" and if you would like to give me valid feedback as to where this is the case (off forum) then i will gladly consider it.

 

I have never hidden the fact that I think the PT is the best product out there in it's field - that is why I chose to become involved with it. Does that make my opinion invalid - I don't think so, but you are of course entitled to your own opinion (one of many)

 

I have not advocated, nor will I, that nobody buys the Ibike - I am, however trying to make sure that people are aware of the issues surrounding it's usefulness as a training aid (which I am qualified to comment on)

 

Anyone buying any product of this type should of course do the research and make an informed decision.

BikeMax2007-02-15 06:45:06

[BikeMax]

Popeye - this may be helpful;

 

http://lists.topica.com/lists/iBikeProPowerMeter/read/

 

Peter

 

[GoLefty!!]

Idon;t claim your opinion to be uinvalid but rather biased for commercial reasons. I;msure if you were not involved with PT at a commerciallevel you'd have an SRM on your bike and that is the dogs stuff isn't it.

 

What I'm saying is that you tend to focus only the negatives of other products whilst breezing over advantages.

 

Not everyone can afford or is interested in being limited by a PT wheel.

 

No one is contesting the fact that a train gauge based powermeter meaures torque, not actually power but TORQUE, nor that this is an Actual measure of the power at the straingauge (not at the pedals since there are losses through the drivetrain due to vibration, friction, rotational mass etc, so PT also approximates power at the pedal cos thats what you say it does.

 

So the debate is who's approximation is closer to the truth.

You say PT and I say it's irrelevant.

 

[Brakkies Sport Fotos]

Thats why I asked from the start that I would like to hear from people who USES the ibike.

 

 

 

They will know the pro's and cons in a "normal" inglish, and nt these newly "out of reach for me to understand" slang ??

 

 

 

I would like to read plain inglish, read those sites, jy kan nie kop of stert uitmaak waaroor hulle bubble.

 

 

 

thanks again for the input.

 

 

 

To make a informed decision? I have to look at the options

 

1) Price between the 2

 

2) The wheel issue - wheel spesific (so you have to decide, you only use it in traing or racing - its powertap)vs ibike = you use it without to hazzle with wheel swaps etc.

 

3) Look at the "cons" of each and decide if its R4000 worth

 

 

 

But, I still believe I must not allow to compare anymore and rather look at the ibike and see if that suits my need. (at least i will be 50% closer on buying the thing)

 

 

[Windbreaker]

 

 

Jet aircraft use Ibike principals to tell them how fast they're flying' date=' how high, how much drag, how much thrust etc, etc so the principal is not new and Newtonian physics have been proven to be ideal for estimating performance of moving bodies in Planet Earth.

 [/quote']

 

GoLefty, your logic is very flawed.

 

Jet aircraft don't fly in bunches and the Newtonian physics thing is completely irrelevant.

 

It's like saying that because the first astronauts used the stars as a primary means of navigation at one point then we should try to incorporate that principle in power measurement on bicycles too.

 

C'mon if you are going to argue for one or the other keep it relevant.

 

 

[BikeMax]

 

Idon;t claim your opinion to be uinvalid but rather biased for commercial reasons. I;msure if you were not involved with PT at a commerciallevel you'd have an SRM on your bike and that is the dogs stuff isn't it.

 

What I'm saying is that you tend to focus only the negatives of other products whilst breezing over advantages.

 

 

 

At the price - with no involvement in PT I would still have a PT on my bike. In fact I had a PT before I became involved - that is why I chose to get involved...

 

The negatives are very important - it is what does NOT work that will piss you off once you have bought the device.

 

[wors]

Lets put it like this then - the Ibike is an indirect measure of power as opposed to a direct measure (such as SRM' date=' PT, Ergomo)

In terms of Ibike being as accurate as PT when the calibration conditions are the same - the calibration conditions are a fundamental variable when riding (weight, draft, smotthness of road etc) and so this statement is largely meaningless when making a comparison of the two.
[/quote']

You obviously don't get it. All of the power devices measure something and then calculate the power. Suggesting that there is indirect measurement for one and direct measurement for the others, is plainly incorrect, as in all the cases there is  just the application of the laws of physics to different measurements.

Weight will also not change meaningfully when riding, and draft is specifically catered for by the ibike. If you do the riding that you want to measure the power for using the same position as when the ibike was calibrated , it will give you as reliable results as a PT.

I can think of enough reasons to rather buy a PT than an ibike, but accuracy is not one of them. 

[Windbreaker]

 

Popeye,

 

Try to borrow an iBike and a PT for a week. Put them both on your bike at the same time. If you are happy with the correlation (i.e. that they give you the same answer) meaning that the accuracy is similar then consider the pro's & cons of each - specific to you.

 

If there is a difference in the data then you really need to consider this carefully before you fork out your bucks - an unreliable power sensor is worthless.

 

Windbreaker2007-02-15 07:08:55

[GoLefty!!]

i) so you've bought an I-bike and tested it and it p*ssed you off and therefore it's rubbish to you?

 

Or

 

ii) are you merely regurgitating the outcomes of the "how do we handle the I-bike threat" marketing meeting held at CycleOp offices?

 

 

 

Which is better?:

Trek Madone SSLx or Time VXRS Ulteam?

[TNT1]

 

 

Which is better?:

Trek Madone SSLx or Time VXRS Ulteam?

 

Exactly the same logic. Nice. Cause for me the answer is neither, it's a Pinarello F4:13