18 replies to this topic

[Hedgey]

Hi guys, I haven’t posted on here for a while.

After having issues with my old speedo I took the plunge and bought one of the 90MPH Smiths digital speedos hoping for a reliable reading

Unfortunately it doesn’t seem to work until I’m going 20MPH or more. The needle stays firmly on the 0 until I hit 20MPH and then it jumps into life and is fine at higher speeds

I changed the speed sensor today thinking it might be that but no luck.

Do all these speedos behave this way or is there something else I can try before going back to the supplier?

Cheers
Elliott

[Shaun78]

Hi,I will say I don't know much about these,but do they need calibration with like tyre size or diff ratio.

[Hedgey]

Hi,I will say I don't know much about these,but do they need calibration with like tyre size or diff ratio.

Hi, I forgot to mention the gauge is calibrated to the car and reads perfectly accurately at anything above 20MPH

[Ethel]

Interference? Play about with the routing of the wiring and/or add some shielding, or improve the earthing of any shielding there is already.

[Hedgey]

Interference? Play about with the routing of the wiring and/or add some shielding, or improve the earthing of any shielding there is already.

I did wonder that. I have taken an earth straight from the battery so it definitely has a good ground. The wiring runs from the back of the radiator next to the wiper motor and into the centre speedo. I can’t think of anything that would interfere but I will add som secondary shielding

[PoolGuy]

They need a sensor with 8 pulses per rev to read at very low speeds. The common 6 pulse sensor shows the issues that you're having.

[Hedgey]

They need a sensor with 8 pulses per rev to read at very low speeds. The common 6 pulse sensor shows the issues that you're having.

Interesting, I’m using this sensor https://www.digital-...plications-p432

This was supplied with the Speedo from Digital speedos

[PoolGuy]

Interesting, I’m using this sensor https://www.digital-...plications-p432

This was supplied with the Speedo from Digital speedos

 

Yes, that's the one that I bought too. I chucked it because it didn't read below 20mph, replaced it with one from Sailes https://sailesmarket...x4h-transducer/ It reads from walking pace. Speak to Matthew he'll make one to suit the Mini, it's about £60.

[Hedgey]

Interesting, I’m using this sensor https://www.digital-...plications-p432

This was supplied with the Speedo from Digital speedos

Yes, that's the one that I bought too. I chucked it because it didn't read below 20mph, replaced it with one from Sailes https://sailesmarket...x4h-transducer/ It reads from walking pace. Speak to Matthew he'll make one to suit the Mini, it's about £60.

Thanks I’ll take a look at them

I’ll contact digital speedos as well as the original speed sensor was supplied as part of a kit from them. I also purchased a second one thinking I had damaged the first one.

[mrmeds]

slightly off topic sorry - mine reads fine.... but never registers full .... do you have issues with that aspect ?

[Hedgey]

slightly off topic sorry - mine reads fine.... but never registers full .... do you have issues with that aspect ?

Is it a digital one as well?
What doesn’t register full?

[PoolGuy]

Fuel gauge?

[mrmeds]

 

slightly off topic sorry - mine reads fine.... but never registers full .... do you have issues with that aspect ?

Is it a digital one as well?
What doesn’t register full?

 

digital..... it only registers 3/4 when full- and the fuel sender has been changed......   also get random flicking of the needle from to max , then min, then back to the correct speed again ( a bit like when you switch engine on )

[Spider]

They need a sensor with 8 pulses per rev to read at very low speeds. The common 6 pulse sensor shows the issues that you're having.

 

There was a sensor that was being sold by Mini Spares for a while that had only 1 pulse per rev and that was the common reason for this.

As PoolGuy suggests, the minimum you need for a Mini is 6 pulses and 8 is better again.

[Ethel]

Interesting stuff,

 

I'm wondering how "digital" it actually is if it needs a minimum number of pulses to register. A speedo not registering under 20 might be tolerable if it's more accurate above that speed, but it has to be useless as an odometer.