Bike "Computer"

[tony6403]

I was interested to see how far I go and at what speed so bought a bike computer from Lidl for only £4.
The sensor and reader need to be within 2mm for it to work. The sensor attaches to a spoke and the reader goes on the forks.
It could not be set up as supplied as there is no way that you can get the two components that close.
I have got it working by , lengthwise, cutting a piece of plastic tube and attaching it to one of the forks to bulk it out and then fixing the sensor.
Not very pleased with this - do these devices all need "Heath Robinson" efforts?

 

[NRG]

No, the sensor on the 8 Function Halfords one I use is a bit over 5mm away from the magnet and it works fine...

 

[10mph]

Apparent Lidl Computer Malfunction was just Stupidity

I bought what is probably the same model of bike computer when I ventured into Lidl for the first time in July to buy a work stand. There was a big gap when the pickup head was aligned parallel to the wheel, but I found that turning it round at an angle I could get the tip close enough to the magnet on the spokes that I got a reliable signal. It probably helped that my forks, being the telescopic ones on my Agattu, are already quite fat.

Generally my engineering efforts, depending on parcel tape to hold things on my bike, are not up to the standard and beautiful simplicity of Heath Robinson eg see this link to pic

My Lidl bike computer stopped working yesterday. Here is the tale:

I was out measuring on the Statford-on-Avon Greenway with another measurer and the race director for the Stratford Marathon. For measuring running races we rely on a special geared counter - avoiding any chance of electronic malfunctions, and with a reading precision of just 8 cm good for accurate length measurements.

I switched on the Lidl bike computer just to check my riding speed - I was aiming for around 10 mph. The speed was zero. It was inconvenient to stop to sort it out so as I rode along in convoy. I was pressing the 3 buttons on the computer to try and get the speedometer display functioning. These days I find it hard to remember the button sequences required for every annoying button controlled piece of electronic kit. With a new bit of kit I can sit down with the manual, or by experiment if the manual is not up to scratch, and get them set up and then remember the key button sequence to switch on and off. What I can't always remember is the button sequence for infrequently used modes.

So it was yesterday, with the Lidl computer going into clock adjust modes etc etc, as with increasing desperation I hit the 3 buttons, all the time trying to maintain my wobble free progression in the measuring convoy. I gave up.

I got home and had a sleep. It then suddenly dawned on me that I have two front wheels for my bike with different profile tyres. I had chosen for this measuring exercise the wheel not fitted with the Lidl magnet!

Where can I buy some cheap extra magnets to fix on the spokes as neatly as the Lidl ones do?

 

[bode]

Where can I buy some cheap extra magnets to fix on the spokes as neatly as the Lidl ones do?

Try this:
Cateye Universal Wheel Magnet

 

[10mph]

Thanks for the tip, Roger, but after adding postage that costs than the original Lidl computer + magnet. So prompted by your post I did an eBay search for something cheaper. I have ordered 3 of these for £3.62 with an additional free one thrown in by the seller.

You have to glue them to spoke with Araldite, so that is not as convenient as the clip on device (which one can of course transfer from wheel to wheel - if you remember). One the other hand this seller has received a lot of very positive comments on his magnets.

 

[lemmy]

There was a big gap when the pickup head was aligned parallel to the wheel, but I found that turning it round at an angle I could get the tip close enough to the magnet on the spokes that I got a reliable signal.

With my Incite cycle computer, that is shown as the proper method of setting it up. In other words, being neatly parallel to the wheel doesn't matter, only the distance matters.

Incidentally, when comparing the Incite with my eTrex Garmin GPS mounted on the handlebars, there is an overall 4% difference in them in both speed and distance. Pretty good, I thought. It is the GPS which shows the slower speed, this with the Incite calibrated to actual measured wheel diameter. Which is nearer to accurate I do not know.

 

[Deleted member 4366]

You can get the whole computer with magnet from here for £2.04:
Bike Bicycle LCD Cycle Computer Odometer Speedometer | eBay

Then you can cut off the sensor (reed switch) and use it as a brake switch if you don't already have one - see my other post

 

[10mph]

I bought 3 of these magnets yesterday for £3.62 with an additional free one thrown in by the seller, and they arrived this morning. I have not glued one to the spoke yet. It holds in position without glue for setup purposes, and it works fine - I have just had to twist the sensor a bit closer.

The more powerful magnet from the same seller would probably need bit less precision in set up, but costs more.

 

[Scimitar]

I was interested to see how far I go and at what speed so bought a bike computer from Lidl for only £4.
The sensor and reader need to be within 2mm for it to work. The sensor attaches to a spoke and the reader goes on the forks.
It could not be set up as supplied as there is no way that you can get the two components that close.
I have got it working by , lengthwise, cutting a piece of plastic tube and attaching it to one of the forks to bulk it out and then fixing the sensor.
Not very pleased with this - do these devices all need "Heath Robinson" efforts?

I got a dud Halford's one where the magnet needed to actually touch the sensor before the speed would register. The retailer replaced it no trouble and the new one actuates if you wave the magnet in the general direction now.
Another one I have is wireless, and it worked perfectly fine with the magnet spaced about 5 or 6mm from the sensor.
It would seem there's a simple lack of quality control so some get through that aren't all they should be.
I'm now left with the original dud one (the seller didn't want it back) and I'm wondering if I can simply use a super-strength button magnet on it.

 

[mike killay]

I fitted a Tesco computer. Seems to work, but the speed read out is delayed and will jump for instance from4.8 to 6.5 rather than smoothly rising and falling.
Is this normal?

 

[103Alex1]

Can anyone tell me please, do all speed sensors need a wheel magnet ? I want to have a speed sensor display and just starting to look into the computer options etc. like Cateye, and other systems like Speedict and Cycle Analyst.

If I need to put a sensor magnet on my wheel it means I'm going to have to take a spoke out to install it and had just got it finished

 

[tillson]

If I need to put a sensor magnet on my wheel it means I'm going to have to take a spoke out to install it and had just got it finished

The magnets usually clip onto the spokes.

 

[Old_Dave]

it means I'm going to have to take a spoke out to install it

Why ?

The magnet is in two pieces... undo the screw, split it into it two parts, place side 1 on the spoke, place side 2 onto side 1 and do the 'screw up'

 

[103Alex1]

Why ?

The magnet is in two pieces... undo the screw, split it into it two parts, place side 1 on the spoke, place side 2 onto side 1

Oh - I SEE ! Thought they had to be threaded on down the spoke from the top and thinking "does not compute, does not compute" . It's been a long day trying to bend the mind round too many concepts with no bits in front of me ... so another misconception corrected to add to the ever-growing list

... and do the 'screw up'

LOL. If it weren't for you lot I'd be doing this a heck of a lot more !