Upgraded RGS Instruments

Can you explain/show how the stepper motor tachometer works to give you a smooth reading. I guess I'm not getting the concept, not knowing what this is.
 
I'm no electronics expert so can't give you the details of how a stepper motor tacho works. They are sold as aftermarket accessories all over the internet however and basically convert the signals/pulses received from the coil or distributer or ecu signal into a rotary movement of a motor but the motor only moves in measured amounts in response to the signal the circuitry sends it. nearly all modern bikes' speedos and tacho's work like this. a tell tale sign is the calibration sweep round the dial and back when the power supply is turned on.
To make it work in the laverda RGS it simply needs to be connected to the same three terminals in the instrument cluster positive, earth and signal, that the old tachometer was connected to. Attached is the ebay page I bought mine from but there are loads of people selling these. the reason I picked this one was the arc of the total needle movement was the closest to the original Veglia dialtacho page.jpeg
 
Very clever Rokka, well done.... there is also for incredible low cost, these GPS speedo's, nothing more than a 5V USB port to power it... AU$15 delivered, work amazing on push bike and vehicles alike..

www.ebay.com.au

Car Digital GPS Satelite Speedo Speed KMH HUD Head Up Display Universal BK | eBay

(※Display mode: KM/H （NOTE: cannot convert to MPH). 4W Solar Panels for Eufy Eufycam Cam E/2C/E/2 Pro Wall Mount ＆ 9.8ft Power Cable. Other accessories demo in the picture is not included. Solar Powered LED Lights Garage Shed Light Garden Indoor Bedroom Outdoor.
www.ebay.com.au
 
20 years ago, Uncle Vena produced this billet machined and hand spun mount and clock covers, i made the digital ( that looked like analouge ). Retained the original clock faces. The speedo and tacho communicated with the iis ignition module, even had a tilt over mercury switch on board.

Project had potential, though most Laverda owners preferred to have their original clocks refurbished, despite eye watering cost... and ongoing issues. Demands on Vena and myself had a slow progress on the project, Vena is a very gifted man, metal work and road riding, been my great pleasure having met him many years ago, including the Snowy GP... j
 

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iis_iis said:
20 years ago, Uncle Vena produced this billet machined and hand spun mount and clock covers, i made the digital ( that looked like analouge ). Retained the original clock faces. The speedo and tacho communicated with the iis ignition module, even had a tilt over mercury switch on board.

Project had potential, though most Laverda owners preferred to have their original clocks refurbished, despite eye watering cost... and ongoing issues. Demands on Vena and myself had a slow progress on the project, Vena is a very gifted man, metal work and road riding, been my great pleasure having met him many years ago, including the Snowy GP... j
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Please encourage him to move forward with this!
Refurb of original clocks is, as you said, very expensive and cannot be sure will get satisfactory results - good if we can take advantage of newer tech while retaining original look.
 
Yes Vena, a very cleaver man and very entertaining!!

My Veglia tach has lost it's needle so needs pulling apart for refurb. Would love to replace the cable with a wire so the stepper motor is really interesting. You up for a little project John??
 
Vena is back in his beloved NZ, the project will not restart, the CNC would be mind boggling to contend with. Perhaps the 3D printer folk may like to take it on... know this technology is clever and advanced. Myself, stay in the old ways, on my lathe, sheet metal rollers, TIG ACDC.... real metal in my hands... been in technologies since late 60's... at some stage my perch will give way, my lathe is a skill valued...

Here is the rear view of the pod Vena produced, the craftmanship is superb, skilled interference fit of the binnacles, should be part of a museum really. Also the one pcb drove speedo and tacho, plus other nice features.... the two needles used to swing 270 degrees on power up, end stop calibration process, common now not so in late 2002, more the nostalgia value. Time to hand over to Rokka... j
 

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Rokka said:
I'm no electronics expert so can't give you the details of how a stepper motor tacho works. They are sold as aftermarket accessories all over the internet however and basically convert the signals/pulses received from the coil or distributer or ecu signal into a rotary movement of a motor but the motor only moves in measured amounts in response to the signal the circuitry sends it. nearly all modern bikes' speedos and tacho's work like this. a tell tale sign is the calibration sweep round the dial and back when the power supply is turned on.
To make it work in the laverda RGS it simply needs to be connected to the same three terminals in the instrument cluster positive, earth and signal, that the old tachometer was connected to. Attached is the ebay page I bought mine from but there are loads of people selling these. the reason I picked this one was the arc of the total needle movement was the closest to the original Veglia dialView attachment 87316
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Keep in mind the original concept of an electronic tacho was for a -350V "spike" ( ignition coil primary, just one of three on the triple motor ) that signal of minus 350V is knocked back to around 0-12V internally on the new tacho, preferred variant is for the ECU to supply a 0-12V direct to a tacho sense connection. Obviously if you apply a 0-12V tacho to a -350V on bike signal, the 0-12v item will be damaged beyond repair, most probable.

Also the triple motor is wasted spark, so you will need to scale the input divider on the replacement tacho to read as divide by two or a two cylinder motor configuration. Even on the series 1 motors. HTH j
 
iis_iis said:
Also the triple motor is wasted spark, so you will need to scale the input divider on the replacement tacho to read as divide by two or a two cylinder motor configuration. Even on the series 1 motors. HTH j
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exactly so. and the tacho I bought from ebay defaults to 2 pulses per rev. so works well for the Laverda. I have an Ignitech ignition. You can set how many pulses you want per rev in the software but the default is also 2. This is useful as most of these tachos will lose their settings and revert to default unless you connect a permanent live to the unit to retain the settings. They have a second + feed wire for this purpose. I'm not keen on permanent connections to batteries on my bikes,( other than maybe a tracker when I'm parking it away from home ) but once installed in the dash it's impossible to reach the configuration button on the back of the unit to reset it every time you ride, so you really have no choice but to connect it permanently to the battery or find a tacho that defaults to the situation that exists in your vehicle, this one happened to be that for my bike.
 
motoddrob said:
I guess something like that could be fitted into a SFC1000 Tack??
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the actual internal components are so small they would fit into almost anything, way smaller than the internals of the original units and weigh next
nothing but you do need to be creative in how you fit it. the screwholes in the original Veglia dial do not match those in the new PCB mounting so it's sadly not quite as simple as it could be but it's really not that tricky with a bit of thought. how I did it for the RGS is in a post I put in the Hints and Tips forum of the ILOC as I used their wiring diagram it seemed only right to put it on their forum so I'm not repeating it all here but anyone handy with a dremel would be capable of fitting it into almost any full sized rev counter housing I would think
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That is quite elaborate pcb and motor drive for the price, did extra well Rokka, take it the tach as shipped is 0-12V input only, perhaps universal voltage span capable, though possible, would require careful signal scaling in a low cost device. Amazing value overall, just like the GPS Speedo for AU$15, delivery included, used here, keep smiling as i watch the readout working.

Do like your voltmeter addition, perfectly engineered, you have some skills there. j

BTW used the LM2917 to replace the oem obsolete f-v chip when rebuilding the oem car pod, touch of Kilopoise on the movement main bearing to damp the oscillations. The speedo i did not engineer any changes as such, sold my Ladies shopping bike RGS... or as Chris ( caustic fame ) described them as "a Spanish galleon" cruel but apt... naughty...must not say things like that... not too often anyway.... a smile here.
 
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iis_iis said:
That is quite elaborate pcb and motor drive for the price, did extra well Rokka, take it the tach as shipped is 0-12V input only, perhaps universal voltage span capable, though possible, would require careful signal scaling in a low cost device. Amazing value overall, just like the GPS Speedo for AU$15, delivery included, used here, keep smiling as i watch the readout working.

Do like your voltmeter addition, perfectly engineered, you have some skills there. j
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that's extremely kind of you, but I don't really. the Volt meter was extremely simple, a couple of hours start to finish including removing the fairing etc, I was really lucky that it fits almost perfectly and was so cheap that it was worth buying one just to chance it.

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Take the win, you earned it.... similar hands here, in the middle of swapping out a Mazda V6 JE series motor, devil of a job keeping hands clean.

The dancing gals like ( insist ) clean hands, as does myself, hard at times without harsh chemicals, mix of soap first and second phase wool wash with eucalyptus oil, and soft scrubbing brush. Free advice not asked for, speciality here. j
 
iis_iis said:
Free advice not asked for, speciality here. j
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I've used a lanolin based 'hand conditioning cream' for years. Applied before breakfast, to fully dry hands. It's fully absorbed by the time you start working. The beauty of it is that your skin will not absorb the oil/grease/grime into the epidermis, so it simply washes off.
Totally eliminates that grime-stained, grease-monkey's hands look.
 
I use Palmolive Dishwashing liquid, just like in the old TV ad. Your soaking in it. It's cheap and easy to get and works really well.
 
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