Tip: Improving cyclocomputer sensor pickup

Here is a very inexpensive tip to improve your cyclocomputers ability to sense speed and/or cadence. It is a fact that most cyclocomputers come with the cheapest magnets available. The are usually housed in some awfully designed package that either bites into the object it it mounted to (usually a spoke) or there are unsightly zip ties all over your beautiful bike.

This little bit of information will enable you to remove a few of those zip ties, allow for better pickup and save a few grams at the same time. The first thing you need is a to find your hobby shop; Hobby Lobby, Michaels, AC Moore, etc. There you will need to pick up a few things, total should be under $10.

The first thing you will need to find is something called Rare-earth magnets, These are super strong magnets made from, you guessed it, rare-earth elements. They are much stronger than the iron based magnets supplied with cyclocomputers. They are also available in a variety of sizes. The second thing you will want is a small package of 3-5 minute epoxy.

We are going to look at the speed magnet first. Here you will want to select the smallest magnet you can find. I chose .25" magnets that came in a package of 10 for under $3.00. The entire package was cheaper than a single replacement magnet from any of the cyclocomputer manufacturers.

The first step is to locate the sensor it self. You will have more flexibility now when placing the sensor since the actuating magnet is so much stronger. You can actually place the sensor/magnet further apart. Now locate where on the wheel the magnet will go. I usually find a spoke on the opposite side of the valve stem, aesthetics mainly.

Mix a little bit of epoxy per the directions on a piece of wax paper or foil. using a toothpick place a dab on one side of the magnet then place the magnet in the proper location on the spoke selected. Take another dab of epoxy and place it on the back side of the spoke so that the spoke is encased in just a bit of epoxy at the magnet location. Hold in place for the 3-5 minutes depending on the type you bought. Set your wheel aside.

Now we will install the cadence magnet. This step is even easier and does not require any adhesive or ties of any kind. Of course this will depend on the type of pedal you are using. If you have a combined sensor such as the Garmin pictured you may want to mark the sensor location based on the cadence magnet first. So here we go! Here I have used .625" magnets, they were packaged in six for under $3.00. Take one magnet and place it on the back side of the crank arm over the rear of the pedal spindle. That’s it, you’re done. No glue, no double-sided tape, no tie straps.

This will work on nearly every pedal unless they use a titanium or other non-magnetic spindle. The magnets are so strong that no matter how many watts you can dial up in a sprint, no matter how bad the weather or wind is, it will not fall off. The strength of the magnet also allows you to locate the sensor further away without affecting its ability to trigger.

There you go, a less than $10 upgrade that also provides you with extra components for that second bike, or second set of wheels. Improves the way the sensor activates and allows more flexibility in mounting. If you find this information useful click on the ShareThis icon below. Now go out and ride!