Okay I purchase, some say a piece of crude "bell f20", but I'm not a crazy biker, so It is good enough for me. When Installing the bike computer How far down on the spoke, front wheel, do I put the magnet and sensor?

It doesn't matter how far down on the spoke.
The magnet needs to be very close to the sensor when it goes around.
Like 1/8 of an inch.

alright thanks for quick reply! I'm going to test it out again.

As 10 Wheels said it doesn't matter. The magnet/sensor only serve to indicate a complete revolution of the wheel and whether its close to the rim or close to the hub the magnet still passes the sensor once per revolution of the wheel. After knowing one revolution has ocurred and how much time it took by the internal clock, the computer can compute your distance traveled and miles per hour and all that other stuff you may or may not want to know. The accuracy of miles traveled depends on how accurately the computer knows the circumference of your wheel. So you need to determine that and enter the best value you can for miles and mph to be true. Be sure to get the magnet and sensor close and tight so they won't get out of alignment once you find the best position. Then your good to go. Just be careful not to run into a tree because of watching the computer.

alright thanks, but I thought, if im totally wrong tell me in a nice way


if the sensor and magnet are farther up, out, however you want to say it, then it takes a longer amount of time to revolve around, but if its closer to the center of wheel it takes a shorter amount of time.

want to know please.

No...the entire wheel completes the same number of revolutions every minute. That means that the magnet will pass the sensor the same number of times every minute regardless of where the magnet and sensor are located. Re-read wmo's post.