Smiths electronic speedo transducer

To adapt an Aprilia electronic speedo to GPS I used one of these.


Its customisable so the calibration procedure works by starting the calibration and adjusting the signal until you see the needle point to 60km/h on the electronic speedo. Its then set so the signal rate is correct.

This looks to be the same but a lot cheaper and the description covers the calibration routine.

 
Jerry,
CnW used to sell a contactless sensor for electronic speedos. I bought one set for my Mk3 which I haven't fitted yet.
A scan through CnW's parts offering didn't reveal the kit, but Matt may still be able to serve you.

CAI's induction speed sensor for cars can be seen here. It may not be ideal for a bike.

A magnetic proximity sensor should deliver the signal needed by the electronic speedo. For instance, this NPN switch:

- Knut
 
Last edited:
Hi Knut,

I chatted with Matt earlier. His one is a different system.

At this point, I will either:

1) Have to convert to a hall sensor type drive (not sure where to get that either for smiths). I think I need to change internals. In fact i did that on my 750, but cant remember where I got it.
2) Or I might try the GPS system. Andover has one. I don't really want to mount it in plain site though. I doubt it works very well if in headlight shell or under the seat.

I'll probably go with option 1 as my original transducer is not available. I am trying to get my MK3 as reliable as possible as its going to be my new touring bike.

Cheers
 
Jerry Doe said:
Thanks. Where did you mount it?
Did you put it on a Smiths speedo?
Click to expand...
GPS unit is at the back of the bike at rear of seat. It does not send a signal to a Smiths speedo but to an Aprilia speedo as the engine is Aprilia and the harness is Aprilia.

[Broken Link Removed]

So I isolated the hall effect wiring and substituted the GPS unit, the key to it working is the calibration, whatever signal count the speedo needs can be set when the needle points to 60 kmph during calibration.
 
Well I looked in my speedo junk box and I got lucky. I have a speedo magnet. No idea where I got it, but now going to use this and go contactless. Off with speedo drive to modify. Thanks everyone for the help.

Smiths electronic speedo transducer
 
Hi Jerry,
FWIW I have an Acewell combination rev n speedo unit …in fact second one as first failed early.
Got it via “Digital-Speedo.Co.uk” who also advertised via UK NOC. Chap at Acewell more accommodating than D-S. Worth going direct I feel.
Best
TBW
 
Thanks.
I am looking on Amazon actually at the sensors. I am pretty sure an M8 will work. I will silicone it in or similar. I know it’s 2 wire 5v. I am now trying to figure out if I need a n/c or n/o open. I think normally open.

Always something hey
 
Jerry Doe said:
Thanks.
I am looking on Amazon actually at the sensors. I am pretty sure an M8 will work. I will silicone it in or similar. I know it’s 2 wire 5v. I am now trying to figure out if I need a n/c or n/o open. I think normally open.

Always something hey
Click to expand...
I’ll look out my Acewell fitting info and if anything relevant I’ll let ya know 👍
 
Jerry Doe said:
I am looking on Amazon actually at the sensors. I am pretty sure an M8 will work. I will silicone it in or similar. I know it’s 2 wire 5v. I am now trying to figure out if I need a n/c or n/o open. I think normally open.
Click to expand...
Reading the fitting instruction for CAI's induction speed sensor, you will see it's of the NPN type, i.e. normally open. It has to be assumed all CAI gauges (whether for cars or motorcycles) are using the same type of input.

- Knut
 
Jerry,
From what I am reading these sensor cables must be a sore spot for these CAI speedometers. I really like the way they work but my cable just went south last week but I was able to get the new upgrade cable from AN before they sold out.Please let us know how you end up with your repair on this.
Thanks,

Mike
CAI makes these Smith gauges
 
At this point, I am kind of over it. Andover don't have any parts, Smiths gauges not much use either. Seems like I might be putting a magnetic gauge back on, which I happen to have. I will keep you posted. I do have another issue there though too. The magnetic gauge has the correct NVT face, but its off a triumph so not as deep as the Norton ones, to fit in the cup, so I need to extend the studs somehow. Stay tuned.
 

Similar threads

uneasy rider
Smiths electronic speedometer wiring
Replies
4
Views
404
uneasy rider
uneasy rider
Jerry Doe
Smiths electronic Instruments
Replies
11
Views
2,152
Jerry Doe
Jerry Doe
robs ss
  • Locked
Smiths Electronic Tacho Error
2
Replies
33
Views
5,019
Torontonian
Torontonian
Tom P
  • Locked
Trouble with Electronic speedo
Replies
13
Views
2,387
marshg246
marshg246
S
  • Locked
Smiths electronic tacho failure
Replies
6
Views
1,648
Fullauto
F
Back
Top