Is cadence magnet necessary when installing SRM power meter?

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hornedfrog
Posts: 235
Joined: Tue Feb 28, 2012 9:13 pm

by hornedfrog

Let me fix that for you:

Epoxy should be overkill?

by Weenie


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ms6073
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Joined: Fri Jul 23, 2004 8:24 pm
Location: Houston, Texas

by ms6073

Although this may not work for certain bottom bracket standards, for our BB86 and BB30 frames, I attach 5mm round flat magnet to the chain stay directly behind the bottom bracket with translucent 3M protective film (occasionally referred to as helicopter tape).
- Michael
"People should stop expecting normal from me... seriously, we all know it's never going to happen"

MoreRideTime
Posts: 128
Joined: Sun Sep 17, 2006 9:09 pm
Location: Canada

by MoreRideTime

I use 3M automotive double-sided tape to hold it on the chainstay. I've done this for a few bikes and never had a problem.

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toiyuet
Posts: 174
Joined: Wed Dec 14, 2011 2:47 pm
Location: Hong Kong

by toiyuet

ms6073 wrote:I have been thinking that the Pioneer sgy-mg910p cadence magnet supplied with the Pioneer Powermeter would be a good alternative:

Image

Wish you good luck.
Even the Pioneer supplied magnet is not 100% workable in full Pioneer system.

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Marlboro Man
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Joined: Mon Mar 15, 2004 12:16 am
Location: Wales

by Marlboro Man

OT, do you have to use SRM's wheel magnet or will any one do?

sungod
Posts: 1702
Joined: Fri Dec 24, 2010 9:37 pm

by sungod

any magnet, as long as it's pointing in the right direction (north/south doesn't matter, just that one pole is pointing at the srm)

you can get a batch of small neodymium (aka rare earth) magnets on ebay for a few £/$/€ then tape/glue one in the correct position

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Marlboro Man
Posts: 97
Joined: Mon Mar 15, 2004 12:16 am
Location: Wales

by Marlboro Man

Ah ok. I have a Cateye magnet but the head unit isn't picking it up so I'll re-pair everything.

Thanks for the assist!

sungod
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Joined: Fri Dec 24, 2010 9:37 pm

by sungod

cateye magnet is probably weaker than a rare earth one, make sure it's lined up with the dot on the back of the srm and within 3-4 mm

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Marlboro Man
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Joined: Mon Mar 15, 2004 12:16 am
Location: Wales

by Marlboro Man

It gives off a little pip when it passes the sensor so that should indicate it's picking it up?

jamesbass
Posts: 114
Joined: Wed Jun 16, 2010 1:19 pm

by jamesbass

I know of 2 people who didn't attach the magnet properly.

Both had the chain come off eventually, catch the magnet, drag it back to the rear derailleur, then tear the entire rear dropout to pieces.

chrispino
Posts: 16
Joined: Sun Jun 10, 2012 7:01 pm

by chrispino

3m VHB tape all day. Had to use this to attach the Pioneer magnets to my frame as very few things stick to my anodized frame. VHB tape has been rock solid for few months now. Been washed a bunch too with no movement. Comes off easy enough when you want it to though

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djm
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Joined: Thu May 14, 2009 12:19 pm
Location: Norway

by djm

Clean frame area with alcohol. Apply a layer of tape. Place small rare Earth magnet over tape, apply desired layers of tape over the magnet.

This makes for a relatively weather proof solution. Also the chain or any other object will not be able to catch onto the magnet, and cleaning debris (all that magnetic stardust!) from the magnet is very easy. I've also used 3M's protective film (your local hardware or car accessory store) as the first layer, with success. When or if you are selling the bike you simply remove the tape and reveal the pristine frame finish.

j0m
Posts: 21
Joined: Fri Jan 19, 2007 11:10 pm
Location: Northern Europe

by j0m

I have a rare earth magnet glued to the inside of the frame. When possible this is a really nice solution.

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djm
Posts: 1403
Joined: Thu May 14, 2009 12:19 pm
Location: Norway

by djm

That would be most elegant..! Next time I'm swapping BB cups I'll dig out the epoxy..

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