Positive earth speed sensor?

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OK, small update.

Matt has been a complete pleasure to deal with. He sourced another sensor & checked that it worked on a positive earth system.

So, Matt (CNW) can supply a replacement cover for the mechanical speedo drive, a sensor mount that replaces one of the rear wheel spacers & a sensor that works with a positive ground system. It uses the 5 disc mounting bolts for the sensor pulse. They are all on the way to Ireland.

I won't have a review of the system till closer to Xmas as it's a winter project for me. I'll take some pics of the install as I know you guys like pictures!!
 
Small update:

Got the 'bits' from Matt + a few other bits for my clutch.

As I would expect from CNW everything is beautifully machined & finished.

The only problem is the sensor holder/spacer & the mechanical speedo drive replacement cover are going to be the shiniest bit's on the bike!! Might need to leave them out in the Irish weather for a few months to try & take the 'zing' out of them!

Won't be fitting anything for a few months but I'll take plenty of pics during the fitting/fettling process.

Here's some pics of the parts:

Positive earth speed sensor?
Positive earth speed sensor?
Positive earth speed sensor?
 
That would be far too shiny for my old gal also. A bit of damp salt air helps rid things of that nasty bling shine also....Doesn't take long at all providing you've some patience.
 
Alternative approach - you now have a few months to bring (or bling) your bike up to spec. :D
 
Happy New Year to one & All!!

OK, starting to look at the electrical side of things for fitting the Smiths Classic Digital Speedo but need some advice.

Just want to be sure about something.

There’s 3 wires on the positive earth sensor I got from Matt:

Blue (Ground, I presume I send the positive feed to this as I've a positive ground system?)
Tan (Sensor Power, I presume I send the neg. feed to this connection?)
Black (Speed Sensor)

I’m using one of the Smiths Classic Digital Speedo’s.

The instructions identify 4 wires for sensor connection and recommend the following connections to their sensor:

White/Black (connect to the White wire on their sensor)
Pink (+5V to red wire on speed sensor, I presume I don't use this one?)
Red/Blue Bands (Alternative speed signal input)
Red (Pull up/Pull down if required for sender, not sure what this means?)

Which of the Smiths speedo wires do I connect to the sensor?

I'm presuming I need to supply a positive and negative connection to the speed sensor + send a sensor connection to the speedo. Do any of the cables from the Smiths speedo send a positive & negative feed?

Don't want to damage anything by just guessing!!!
 
Click, I can’t help re the wires cos I used the Smiths pic up.

Maybe it’s too early on a Sunday morning for my small brain...

But... how does that speedo drive cover work? Is it stationary or rotating? Where are the trigger magnets?
 
Fast Eddie said:
Click, I can’t help re the wires cos I used the Smiths pic up.

Maybe it’s too early on a Sunday morning for my small brain...

But... how does that speedo drive cover work? Is it stationary or rotating? Where are the trigger magnets?
Click to expand...


The cover is just a cover, no gubbins in it. The sensor is the same setup you have but it’s positive earth & uses the 5 bolt heads securing the rear disc as it’s sensor input (no magnets required!)
 
click said:
Happy New Year to one & All!!

OK, starting to look at the electrical side of things for fitting the Smiths Classic Digital Speedo but need some advice.

Just want to be sure about something.

There’s 3 wires on the positive earth sensor I got from Matt:

Blue (Ground, I presume I send the positive feed to this as I've a positive ground system?)
Tan (Sensor Power, I presume I send the neg. feed to this connection?)
Black (Speed Sensor)

I’m using one of the Smiths Classic Digital Speedo’s.

The instructions identify 4 wires for sensor connection and recommend the following connections to their sensor:

White/Black (connect to the White wire on their sensor)
Pink (+5V to red wire on speed sensor, I presume I don't use this one?)
Red/Blue Bands (Alternative speed signal input)
Red (Pull up/Pull down if required for sender, not sure what this means?)

Which of the Smiths speedo wires do I connect to the sensor?

I'm presuming I need to supply a positive and negative connection to the speed sensor + send a sensor connection to the speedo. Do any of the cables from the Smiths speedo send a positive & negative feed?

Don't want to damage anything by just guessing!!!
Click to expand...


I’d say don’t connect anything until someone with a bit more knowledge and the instructions in front of them chimes in here.
 
Suggest you ask Matt as it looks to me like the Smiths can feed either 12V (Red ?) or 5V (Pink) to the sender and the 12V will fry the CNW sender if its a 5V sender.
 
click said:
The cover is just a cover, no gubbins in it. The sensor is the same setup you have but it’s positive earth & uses the 5 bolt heads securing the rear disc as it’s sensor input (no magnets required!)
Click to expand...
Got it!
 
kommando said:
Suggest you ask Matt as it looks to me like the Smiths can feed either 12V (Red ?) or 5V (Pink) to the sender and the 12V will fry the CNW sender if its a 5V sender.
Click to expand...

Thanks for the advice, I won't be 'messing around' willy nilly connecting wires just to see what happens :rolleyes:

I've asked Matt the same question & I'll hopefully get a reply next week. I'll also rings Smiths tomorrow to see if they can identify the various sensor wires coming from their speedo and what they feed.

More anon!
 
Triton Thrasher said:
I’d say don’t connect anything until someone with a bit more knowledge and the instructions in front of them chimes in here.
Click to expand...

Good advice which I will take :)

Just back from a spin on one of my other bikes, nice cold fresh morning, one way to wake up on a Sunday morning!!
 
I am in the process of installing a Smith speedo on my ‘74 Commando.

I am using the cNw speedo drive.

As understand the poorly written Smith instructions, I will connect the White/Black wire from the speedo tp the BLACK wire from the cNw sender.

In Matt’s instructions he writes the TAN wire is “12 volt power”. Is that +12 volts or -12 volts?

Smith Instruments should enlist the services of a technical writing to produce a proper installation manual.

Aside from the poor instructions, it would be nice if their gauges had a connector instead of pigtails for connection.

I am using DIN connectors under the tank to make removal easier.
 

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arch said:
I am in the process of installing a Smith speedo on my ‘74 Commando.

I am using the cNw speedo drive.

As understand the poorly written Smith instructions, I will connect the White/Black wire from the speedo tp the BLACK wire from the cNw sender.

In Matt’s instructions he writes the TAN wire is “12 volt power”. Is that +12 volts or -12 volts?

Smith Instruments should enlist the services of a technical writing to produce a proper installation manual.

Aside from the poor instructions, it would be nice if their gauges had a connector instead of pigtails for connection.

I am using DIN connectors under the tank to make removal easier.
Click to expand...

Thanks for the reply.

I plan on using some type of multi-pin connector, I have a few to choose from.

Just need to wait on more info. about the wire designation on the Smiths Digital Speedo!
 
I do not have Matt's sensor - I used the magnetic pickup sold by Smith's and a magnet glued to the rear brake casing.
Simple. No power involved with the sensor.
I agree that instructions from Smith's are not good and the tiny connector wires are not ideal to make connections.
BUT - the good news is this...
I installed both gauges when my bike was positive ground.
I have since converted to negative ground and the connections are all UNCHANGED.
ie. - power and ground connections are still power and ground!
 
click said:
Thanks for the reply.

I plan on using some type of multi-pin connector, I have a few to choose from.

Just need to wait on more info. about the wire designation on the Smiths Digital Speedo!
Click to expand...

I would be interested in seeing what connectors your use.
 
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