Spoke Magnet Sliding

[pjboyle]

Has anyone had experience with the magnet for the speed sensor coming loose? I installed the iBike today, did all the cals + 3 CD, then set off for an area to do CDs and o&b 4 mile. About a mile form the house I lost speed reading and realized the magnet had come loose and migrated to the rim. Stopped and retightented, but within 200 yds it was loose again. I found an aluminum foil gum wrapper on the ground and gave a few wraps around the spoke, then forced the magnet assembly over this and retightened. This held for the rest of the ride (almost 40 miles). I have flat aero spokes and it seems like they are not thick enough for the magnet assembly to keep a good hold. I'm thinking of trying my old Polar magnet, which clamps around the spoke with the screw at the side, vs the screw trying to set directly against the spoke. Either that or some 3M sticky sticky on the spoke under the magnet.

[racerfern]

I use the magnet supplied with my Mavic SL wheels. It has a little plastic holder with a screw that hasn't budged. Being a flat spoke, I never tried the magnet supplied with the iBike.

[michaeltop]

Best fix for flat spokes is to drop by a Raidoshack and pick up the small ceramic super magnets. Epoxy or superglue onto the spoke.

[pjboyle]

I went back to the Polar magnet I had removed in switching to the iBike. It works fine and is less than half the size and is more aero. It holds well on flat spokes.

[Isaias]

This is sort of interesting, because the wheel magnets that I received with my wireless kit had a spoke magnet that accomodates flat spokes. I run Topolino wheels and they have the flat carbon fiber, kevlar covered spokes. They are flat and thicker than the bladed aero spokes you would normally see. The spoke magnet that I received from Velocomp worked perfectly.

In the past, whenever I've had magnet migration issues, I'd just put a small bit of ShoeGoo on the magnet/spoke interface. Once it cured, no more magnet migration. Unlike Super Glue, the ShoeGoo can be stripped off by hand if you need to move the magnet later.

[chrispy]

I use the Cateye magnets, which will work on either flat or round spokes. They're nice, low-profile magnets.

I put a drop of blue loctite on the magnet and screw it down nice and tight against the backing piece (there's a "v" in the round-spoke side; the other side is flat).

[sl@enposte.net]

http://www.rare-earth-magnets.com/detail-ID-87.html, about $10 (plus shipping) will get you 40. Buy a good glue (Gorrila glue works for me.)

I usually glue two onto the spoke, side-by-side.

Cheap and aero.