Help! Need accurate way to measure cadence...

Help! I need an accurate way to measure my pedal cadence. I don't want to do the "count for twenty seconds, multiply..." thing. I'm looking at the Polar cadence sensors, but they require a different HRM model than the one I have. Does anyone know of something similar, but that I could get without a new HRM? Thanks for a speedy reply!

 

Some of the units used for speed and distance mesuring have this function.

Like cateye astrale costs about 30 euro's.
Shimano flightdeck also has this function, but these mesurements are made upon your speed so you get the reading of the rpm you should peddal to maintain your speed given the gear you are using. Advantage only one sensor and in the expensive version no wires.

 

This is an awesome computer no wires. Works great.
http://www.performancebike.com/shop/Profile.html?SKU=16192

I guess they dont carry it anymore at Performance. Just to ref. the pic.

 

If it's just a one-off thing you can use a basic cyclometer with a speed sensor to measure cadence. You just put the sensor and a magnet on the crank, instead of the front wheel.

You need to do a bit of working out to get the display calibrated though (I would guess you'd want it to have 10rpm of cadence coming up as 1.0kph; and mess with what you put down as your wheel size etc. to get it to do that.)

A bit of maths, trial and error involved, but it can be done.. I remember seeing a posting either here or on one of the Usenet groups about how to do this, and the numbers to put in.

Or else you can just buy a cyclometer with a cadence sensor. I've seen a couple of Cateye (and other brand) models that do this at the LBS that aren't too expensive.

 

The Shimano Flight Deck is good but requires compatible STI levers which you may or may not have. The best and cleanest computer with cadence is the Avocet 45TT ($50 U.S.). Make sure you get the cadence option.

The Vetta MGSuarez refers to is something to consider, but I have never seen one or know anyone who has. Wireless cadence is the way to go if possible, because all the wired cadence kits out there are a little ugly and bulky, but having the data is what is most important.

 

I had the Sigma BC1400 cycle computer before switching to my Polar. As J-MAT mentioned, the wiring doesn't look nice, but it works. Sigma now brought out the new BC1600 (looks nice), but it seems to have the same functions. You check the Sigma computers here.

 

Accurate? You need to get unit that actually has a sensor and a pickup on the crank arm to count. All others simply estimate.