Computrainer Cadence Fix?

harrast

Can anyone point me to a fix for the computrainer cadence not working issue?  Here's the history: Bought my computrainer used a few years ago.  Cadence worked intermittently then quit altogether.  I never really worried about it until my son started to ride and I wanted to give him some stat's on his cadence and why he should pedal a little faster.  I am also anal about having working equipment.  So I cleaned all the electrical contacts with an aerosol, but still no cadence.  I'm doing my testing by manually passing a magnet over the sensor while I watch for recognition on the head unit.  I have tried the computrainer magnet as well as other magnets, but no cadence.  I have also tested the sensor on the bike in multiple positions varying the distance from the magnet and the fore and aft position of the sensor.  Nothing.  Not even a spark.  Any ideas?  BTW, I have a second sensor (also used) and have gone through the same drill with no better results.  Is it possible that both sensors are bad?  Should I try a new sensor.  Is this a design issue that cannot be fixed with new parts?  Looking for the wisdom of my elders.  

Al Truscott

The CT head unit/controller is notorious for developing problems at the input plugs (in the controller). CT blames the user for this, either being too rough inserting/removing, or sweating on the unit, causing water damage. My HR plug fritzed out after a year or two. Later, when the PC plug went, I had to pay $250 to get a new controller. Within a year, the HR blew again. Next, the transformer on the power cord failed. At that point, I just opened it up and resoldered some wires. I'm waiting for failure again so I have an excuse to buy a Kickr. But despite duct tape holding the transformer together, electrical tape holding the wire to the transformer, and a stellate crack in the glued on clear plastic over the controller screen, the thing refuses to die. Maybe I'm not perspring enough.

Since I also have a powertap/ Joule combo, I use that for HR and cadence. Saves a couple of wires.

robin sarner

might try new sensor but if two of yours not working...

 

work around of cheap wired bike computer?

 

harrast

Al, you'd better install a webcam in your cave. I think the dog may be going down there and abusing your trainer. Seriously, I hadn't thought about the plugs in the head unit being bad, but that could be it. I guess my options would be open the head unit and see if I can fix it or to get a new head unit. I know there are other ways to get cadence, but I want to use the data in my Racermate One software, so it has to come from the computrainer. Anywho, you've given me an idea. Thanks.

kevhill

Yeah I had same issue, needed to send head unit back to get ports fixed.  Didn't last long before stopped working again. Had given up on HR until I started using TR, now I can link the Garmin cadence sensor in that which works all the time.

kevhill

Yeah I had same issue, needed to send head unit back to get ports fixed.  Didn't last long before stopped working again. Had given up on cadence until I started using TR, now I can link the Garmin cadence sensor in that which works all the time.

harrast

I'm coming back to the well of knowledge.  I got around to testing the cadence sensors for my Computrainer.  From what I read on the Computrainer forum, the sensor circuit is open (high resistance) until a magnet is applied, and then it is closed (low or no resistance).  So I tested the sensor circuit (tip to sleeve on the plug) with (and without) the magnet and it was always open.  I have two old sensors around and they both tested bad (always open)--according to this test.  So, before I order another sensor from racermate and waste $40 of my children's inheritance, any other thoughts?  Any electrical engineers who care to shine some light on this deep topic?  Any hacks (like me) with some SWAG?  I'm open to all ideas on this.