Fitting trip computers - 2 tips

  1. If you fit a trip computer which reads from a magnet attached to a spoke (as most do) then fit the magnet slightly AHEAD of the crank on that side.
    I have had this annoying pinging noise for a while now and thought it was a loose spoke, as it only happened at times of maximum torque - like cresting a hill. It turned out that either the wheel was flexing or, more likely the forks were, when I was pushing hardest on the pedals, and the magnet was catching the ‘reader’ attached to the fork leg. That was with the magnet randomly positioned on the wheel - coincidentally, a few degrees behind the crank. Moving the magnet has cured the problem.

  2. I was looking at wireless computers in my local sports store. They transmit a radio signal to the computer unit, so there is no need for a wire. My idea was to keep the computer in my pocket or on a wrist band for easy reading when I was riding.
    I sneakily took the instructions out of the pack to see whether the unit would work on a 36 inch wheel, and noticed a reference to the computer having to be positioned within 30 degrees of a line passing vertically up from the ‘reader’ on the forks.
    Presumably the transmitter only transmits in a narrow cone like this to stop it interfering with similar computers on other cycles travelling in a group. However, it seems to me that this level of precision would be unsustaiable on a unicycle, so I guess these wireless devices probably won’t work for us.

(Incidentally, why are they called ‘wire free’ now, when ‘wireless’ means exactly the same, and was a perfectly good use of the language? Mutters darkly about things not being what they used to be…)

Re: Fitting trip computers - 2 tips

Because oldies were wondering if they could listen to the radio at the same time (wireless=radio)? The 30 degree cone should be wide enough to take into acount the computer being in your pocket. If not maybe you can alter the angle/position of the reader, you might need to use some extra cable ties or something as they tend to only fit in one position relative to the fork.

I’ve used my wireless computer on my bike with it in my pocket and it seemed to pick up about 20-30% of the readings (judging by the distance in measured) and that was well out of the 30 degree cone, so maybe there’s more leeway in these things than they let on.


I was looking at polar heart monitors at the weekend. They have a couple of models with built in cycle functions. These are wrist mounted and wireless. The signals are coded to not interfere and the transmitter seems to work from anywhere.

Quite expensive, though…