Mounting cadence magnet on crank arm with indented inside

Triathlon Forum
1

Hi Guys,

My wife’s bike has crank arms which aren’t straight on the inside. It’s sort of a u-shape profile. This has caused the magnet for the cadence sensor to come off.

Does anyone have any suggestions on how to mount a new magnet?

Thanks.

2

Hi Guys,

My wife’s bike has crank arms which aren’t straight on the inside. It’s sort of a u-shape profile. This has caused the magnet for the cadence sensor to come off.

Does anyone have any suggestions on how to mount a new magnet?

Thanks.

I used electrical tape to secure my magnet to my crank arm before I got my power meter that measures cadence. Just did about two to three passes nice and tight. No issues for about 9 months I had it like that.

3

Epoxy or superglue the magnet inside that channel? Or even strong double sided tape cut to fit?
Make sure the sensor still picks up the magnet.
Potentially get a strong rare earth magnet. I’ve seen those sold to fit on the end of a pedal spindle; if your sensor can be positioned to match.

4

Thanks for the suggestions. I’m thinking that a combination of epoxy and tape might be the way to go.

5

Which cadence sensor are you using? I’ve got a GSC-10 and just use a neodynium magnet that just sticks onto the pedal spindle on the inside of your crank. Takes a little bit of fiddling with the sensor position to get it working perfectly, but it’s a nice clean setup. Looks like this and you can pick them up on eBay or Amazon real cheap.

http://i.ebayimg.com/00/s/NzY4WDc2OA==/$(KGrHqNHJBkE-gORnzvqBPvL7oLiLw~~60_35.JPG?set_id=8800005007

6

Bontrager makes cadence magnets built into rubber sleeves that slip over a crank arm. They offer these in at least a couple of thicknesses for varying magnet clearance.

7

Which cadence sensor are you using? I’ve got a GSC-10 and just use a neodynium magnet that just sticks onto the pedal spindle on the inside of your crank. Takes a little bit of fiddling with the sensor position to get it working perfectly, but it’s a nice clean setup. Looks like this and you can pick them up on eBay or Amazon real cheap.

![http://i.ebayimg.com/00/s/NzY4WDc2OA==/$(KGrHqNHJBkE-gORnzvqBPvL7oLiLw~~60_35.JPG?set_id=8800005007](http://i.ebayimg.com/00/s/NzY4WDc2OA==/$(KGrHqNHJBkE-gORnzvqBPvL7oLiLw~~60_35.JPG?set_id=8800005007)

+1 This is what I’ve done and I have had 0 issues. Just make sure you get the one with the proper diameter to fit inside the crank arm.