Powertap

[bruce]

Hey, nothing like a little bit of academic debate to get the juices flowing

 

Seriously though, one would assume that a person has a left/right leg imbalance do to an inherent structural/muscular (i.e. biomechanical) problem.  It would be interesting to see if the two legs would progress at different rates - my gut feel would be that the problem is structural and doesn't change.  But then I'm an engineer not a physiologist so I could (and probably am) way wrong on this.

 

There is an interesting discussion regarding the benefit of weight training to endurance cyclists in which it is evident that doing weight training is of no benefit to endurance cyclists.  Apparently the force that is applied per pedal stroke is equivalent to 25kg's leg press.  Now, both legs are more than capable of applying this type of force, so that only reason I can think that an imbalance would occur is that there is structurally something wrong which probably doesn't change through training.

[bruce]

How much is the Ergo PM Windbreaker? I'm what ppl call goofy since my left leg is the stronger one but I write with my right hand' date=' anyway, so you saying my reading would thus be out by a few watts?? How many is a few?[/quote']

 

My testing gave me about 2.5% difference between the two PM's at 350watts.

 

Drop a note to Marco Swart at cycletech@telkomsa.net and ask him to give you a price.  Tell him bruce sent you and he'll increase the price   Na, only kidding!!

[bruce]

Take a look at http://www.ergomo.net/FAQ-_156.html

There is a specific discussion regarding the one-leg situation - however to expect that the company would say it causes major problems would be expecting a bit much

[Marius]

found a nice little link, still busy ready: http://www.thebikeage.com/ergotest.htm

[Windbreaker]

There is an interesting discussion regarding the benefit of weight training to endurance cyclists in which it is evident that doing weight training is of no benefit to endurance cyclists.  Apparently the force that is applied per pedal stroke is equivalent to 25kg's leg press.  Now' date=' both legs are more than capable of applying this type of force, so that only reason I can think that an imbalance would occur is that there is structurally something wrong which probably doesn't change through training.

[/Quote']

 

I read something along those lines too and I also considered that my actual bike setup was playing a role if not THE reason for the difference between the development of the legs. On the other hand as a kid I had weak knees and the left foot was very pigeon-toed so you could be spot on.

 

I've started to make small adjustments to my cleat positions but I also concentrate on making sure that I try to keep the pedal strokes even. I'm still not sure that my set up is right.

 

I bet some people are reading this thread and wondering "what are these guys on? - where are the days of just getting on the bike and riding". Half of the fun for me is monitoring exactly how I am progressing,  understanding why things are happening and making sure that the little time that I get to train is as efficient that I can make it.

 

 

[bruce]

found a nice little link' date=' still busy ready: http://www.thebikeage.com/ergotest.htm[/quote']

 

That's a pretty old Ergomo - certainly there are no data download problems using CyclingPeaks and the current Ergomo.

[Marius]

http://www.biketechreview.com/archive/pm_review_2.htm

 

I don' t get Polar, they must have pretty deep pockets so why the hell can't they engineer a decent Power Meter?!!?!?

Marius2006-11-01 04:38:31

[bruce]

All the reports I've read about the Polar indicate that it doesn't like being on an indoor trainer.

 

A new version is coming out soon apparently - I think it is also wireless and solves the indoor trainer problem.  And the problem of errors when on the biggest rear sprocket.

 

My first PM was a polar - very difficult to set up, and I never could get it to read consistently across all sprockets on the cassette.

[bruce]

http://www.biketechreview.com/archive/pm_review_2.htm

 

I don' t get Polar' date=' they must have pretty deep pockets so why the hell can't they engineer a decent Power Meter?!!?!?

[/quote']

 

I have a suspicion that it is something to do with patents.  I know the SRM patent runs out next year, which means companies like Shimano will be able to get into the PM market.

 

Every power meter on the market uses a different mechanism:

PowerTap - Rear hub

Ergomo - BB

SRM - Spider

Polar - chain speed and vibration

iBike - wind speed, accelerometer, gradient etc.

[Windbreaker]

 

Likewise, my first PM was a Polar and I had exactly the same problems. I was a little disappointed by Polar - the company. I suppose that they have a business to protect but I was on a wild goose-chase for a long, long time trying to work out what I was doing wrong when the whole time the problem was intrinsic to the device. I think that the concept is fatally flawed - there are just too many variables.

[stringbean]

Would love to have a PT ,but the price.My lbs tells me that powertap are now selling direct to the public with prices starting around R8500 for the bottom of the range PT.You have to then add the cost of building a wheel as well.Ergomo rrp is about R16500.That's a LOT of money.

[Dr. Seuss]

 

dont know too much about physics,  but by the sounds of it the current polar must be the most inaccurate of the lot - chain vibrations?  on our rough roads it must really skew the readings.

 

stringbean - ERGOMO goes for R13,500 - http://www.cycletech.co.za/ - this is with the cranks.

 

 

 

Dr. Seuss2006-11-01 07:28:51

[Marius]

Thank you for your interest in the PowerTap system

Here is some basic information about the various models:<?:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

Current Pricing:

PowerTap (Standard): R5999

PowerTap Pro: R6999

PowerTap SL: R8499

[bruce]

So that is R8500 for the top of the range, not the bottom of the range.

 

Chat to Adrian/Frank they got me a second hand (demo version) of a PT Pro built into a wheel for R5000 over a year ago.  And they gave me a 6 month warranty on it - not that it was required!!

[stringbean]

 

Thank you for your interest in the PowerTap system

Here is some basic information about the various models:

Current Pricing:

PowerTap (Standard): R5999

PowerTap Pro: R6999

PowerTap SL: R8499

Are those prices inc vat.

Where can i get a powertap sl for R8499

 

[BikeMax]

The PT standard is also a good option, and represents good value for money as a very accurate and high quality entry into the power meter market. A decent wheel build can be had for ~R500 and so for the price of a set of Ksyriums or similar, you have the best training tool available.