Where can I find the best price on a PowerTap system?

Scott

can I add the same question but for SRM powercranks??? training on power is a great idea but just a bit too expensive for most.

Don't forget with powertap to add in the cost of the wheel you'll require. That 's the drawback for me.. do you put it on a crappy training wheel and use it only in winter or a decent one for racing but risk damage/increased wear in the offseason??

Ta, doozer

_________________
Dance you cares away, worries for another day, dance your cares away, down at fragglerock.

Can I also hyjack teh thread.

How does the power kit for a polar HRM work?

how does a powertap and SRM crank work in measuring power?

The answers for the last questions can be found with google. I can't explain it in good English.

A powertap price in the netherlands is very high. It's 1299euro according to cervelo.nl which distribute the cycleops products. Maybe some shops will sell it cheaper. I am going to check that this month. I am interessted in the powertap myself.

I have seen the powertap for 1099euro in germany (rose versand).

And in America the price is 899dollar (on their website).

Do other people know what price for powertap pro is in belgium, germany or the netherlands?

Bontrager makes a Power-Tap wheel:
http://www.bontrager.com/roadwheels/detail.asp?id=167&pt=10

Standard: $1099
Pro: $1250

That looks good if you like bontrager wheels.

I prefer the black powertap hub with the powertap pro computer. And then building it with 32 sapim cx-ray spokes and the Swiss R1.1 rim.

The Polar system measures the tension and speed of the chain. Chain tension in Newtons multiplied by chain speed in meters per second gives Watts of power. The chain tension is measured by the chain's frequency of vibration, hence the need for chain weight and length between the gears. The sensor functions like an electric guitar pick up. An application specific integrated circuit or PIC derives tension from the frequency of vibration and filters out all but the fundamental harmonics. Depending on functions requested, processiing takes between 2 and 4 seconds.

PT and SRM work by measuring torque. Torque in Newton Meters multiplied by rotational speed in radians per second (2 pi radians per revolution) gives Watts of power. In each, there is an element which all torque is transmitted through. On this element is a strain gauge which measures the elastic response of the element to torque and represents it as a change in resistance.