I use a Cateye Astrale computer for speed and cadence. I have a magnet on my crankarm (obviously) and one on my rear wheel.
Yesterday I took my new Corima 4-spoke rear wheel and deep rim front wheel for its first test ride and it took me a minute of playing with my computer to figure out why I wasn’t getting any speed. Duh. Not so smart sometimes!
So, here’s the question? What’s the solution so that I can swap easily between wheel sets? Probably can’t put a magnet on a 4 spoke (too far away from the pickup).
Is there a bike computer that does speed pickup on the front wheel where I can mount the magnet on one of the bladed spokes of my front race wheel and normal everyday Rolf Vector Comp and still have a cadence pickup? Do I have to go wireless to get cadence and front wheel speed? The problem is I like rear wheel speed for riding my trainer to get a correlation with my effort (trainer is a Cyclops Fluid)
Is there a way to still have rear wheel speed when you have something like a tri-spoke, 4 spoke or disc?
BTW - the wheels rock! They really “felt” faster - acceleration, speed maintenance, etc. Hope they’re worth it for IMG next month!
A magnet is a magnet. If you want one that will work on the 4 spoke, just buy a bigger magnet and slap it on one of the spokes - you can use silicone (I have on my cranks) and maybe a little electrical tape.
Cheaper than a new computer, better than any of the wireless stuff, too.
I ran into the same problem this spring with my Renn Disc…I simply mounted a magnet directly to the disc surface with heavy duty double sided tape (maybe you can find another crank arm magnet the can be held in place by the sticky tape and zip tie for the Cormia). Now as for the gap, I just made it so that I could rotate the sensor inward by twisting it on the chainstay (you might need to loosen the mounting bracket just a smidge to do this). Once you find the right tightness for the bracket all you do is twist it inward when you mount the race wheel until you get reception…then twist it out for you training wheels. Sounds kida complicated but it really is simple…
For carbon spoke wheels like this I glue a magnet in the area near the valve hole. For disk wheels I glue a magnet to the inside of the wheel next to the valve hole. I bought some 1/2 inch diameter rare earth magnets off of EBay, about a dollar apiece.
The simplest and best solution is to go to Radio Shack and get one of their tiny (1/8 inch?) rare earth magnets and superglue it to your wheel at an appropriate spot. These babies are super tiny, but more powerful than the standard magnets. I do this with all my discs and H3s that need magnets. This solution works well for your cadence magnet too, as opposed to having to do a comparatively ugly zip tie or electrical tape job.