Russ' Do It Yourself Home Workshop

Finding Fixes to Just About Anything and Everything

Archive for April, 2016

Repairing the Eddy Current Brake on a LifeFitness x5i Elliptical

Posted by Russell Wright on April 19, 2016

Well, I’ve now done this twice and I never published the pictures I took the first time, so here goes. 

What you may notice is the resistance is always higher than what you want…or what you remember the least resistance to be.  In fact, at one point, you might have heard the "pop" or "snap" while using your elliptical and notice the resistance no longer adjusts as low as it should.  You’ve come to the right place, and I’ll show you how to repair this for $10 or so.

So what is an "Eddy Current Brake?"  Well, it’s the magnetic part that creates the adjustable resistance on your machine.  In particular, we’re talking about the FB1 manufactured by Chi Hua in Taiwan.  To break (brake…LOL) it down in simple terms, eddy currents are created from the magnetic flux (of magnets) passing through a coil of wire (conductor).  Basically, you have a generator that creates small currents in a conductor that are essentially short circuited and turned into heat.  You can read about it at the source of all knowledge…Wikipedia.  This is what makes the drag force on your elliptical…you know, the thing that makes your legs hurt and sweat pour from your body.  Check it out on their web site and use your web browser’s translate feature.

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Well, here’s what happens.  The blue actuator pulls and releases the cable based on the level setting.  This makes the white part in the green ECB (Eddy Current Brake) travel back and forth, which moves the magnets away from and closer to the flywheel, generating your resistance.

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Unfortunately, after some period of time, the cable wears and snaps in two.  This is shown after removing the green part (essentially the stator). 

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Getting the green part (stator) out (assuming yours is green, too) requires some mechanical work, but it’s not too hard…just takes some time.  You have to remove the flywheel.  Release the tension on the belt by loosening the nut on the tensioner.  Then you have to remove the flywheel nuts and the tensioner bracket.

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You also have to remove the stator locking bracket to get it out of the way.  The actuator cable is easier to remove from the blue actuator side first by pulling and unwrapping it from the nylon spool.

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What you are going to have to do is fashion a new cable to replace at least the one that broke.  Maybe two, if the other is worn and fraying.  I did this by purchasing a bicycle shifter cable ($5) and grinding down the barrel end with my Dremel tool to make it the correct diameter and length.  The ball end of the cable is not very critical.  It simply needs to NOT pass through the hole in the magnet.  You can pass the barrel end through the hole when threading it in place.  The replacement for the ball is a cable clamp that has been "swaged" in place using a crimping tool.  I used my ratcheting electrical crimpers, but you may want to opt for something more professional, like these hydraulic crimpers.

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Here are my notes I took with my calipers.  Notice the leftover Christmas notepad paper. 

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I didn’t get any pics of the stator taken apart, but it’s pretty easy to remove.  Two allen set screws hold it to the shaft.  Loosen these and pull it out…you’ll feel the magnets wanting to keep it in the flywheel.  Then there are some black phillip screws holding it together and the four silver screws that hold the thingamajiggy with the allen set screws.  Inside you’ll see the white plastic actuator that connects all the cables.

When you are done you’ll have something that looks like this.  Not really pretty, but very functional.

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Posted in Misc Repair | 14 Comments »