RGS rev counter

[tom3c75]

The needle on my RGS rev counter is very erratic, unsteady at idle and worse at speed, when it flicks back and forth across the dial.

I had hoped that fitting the Ignitech ignition would fix it, but it has not.   

I've trawled through previous posts on this subject and now plan to check for missing counterweights on the needle.

My question is: Where exactly are these weights within the rev counter mechanism, and how deep do I need to delve in order to reattach them if they are missing?   

Presumably the weights are not attached to the visible part of the needle, but to a part of the needle spindle that is buried below the underside of the rev counter face.  Does the underside of the needle have an arm to which the weights are attached?  And must the cover of the rev counter mechanism be removed to get at the weights?

Grazie molto.

 

[2622]

If you have fitted an IGNITECH then you need to install a filter as the wave forms are different.. so would suggest that first. Otherwise if you still an issue then you need to remove the unit top cover and the lift out the tacho. You will see the weights but also might be the dampening fluid that needs replenishing.. hobby store is your friend there for the fluid

Oh and also they used two different tacho set up some have a dash pod which can be handy to dial them in.. the one of the RGS usually doesn?t way up till I?ve done some miles but then comes good well as good as a Veglia can ever be.

Good luck 

Of course you could always just send it to Jason to sort it for you then you know its gunna be spot on 

 

[tom3c75]

Thanks Brett.

What does the filter consist of, and is there a spec for it?

Tom

 

[Rob]

The filter comprises a resistor and capacitor - see
https://www.laverdaforum.com/forum/index.php/topic,84845.msg203498.html#msg203498

Subsequently it was suggested that the wiring should be altered
https://www.laverdaforum.com/forum/index.php/topic,100119.msg443427.html#msg443427
I can confirm that this alteration does indeed seem to work better.

BUT - did you swap your revcounter feed from the original factory BTZ connection (green/violet) on to the Ignitech revcounter output (terminal 15)?
If not, then you should.

Assuming you have - and from your description of the needle movement - then yes, it sounds as though one or more of the lead weights have dropped off.  You need to remove the instrument cluster from the bike, remove the odo reset knob, remove the curved perspex instrument cover, remove the revcounter needle, unscrew the graduation plate and then you can remove the revcounter from its housing. If you look carefully at the mechanism you'll see (3 from memory) short arms that have a small loop at their ends.  That's where a tiny lead weight should sit.  You may find one or more loose inside the  instrument cluster.

 

[tom3c75]

Thanks Rob, that's useful info.
I did not pay much attention to Kristian's post as it referred to a DMC set up.

So, if I fabricate a filter according to Drikko's post, would the wiring, taking account of Kristian's post, be as follows:
1.  A resistor connecting the wire from the Ignitech terminal 15 to the green wire to the tach.
2.  A capacitor placed on the green tach wire (after the resistor) and leading to ground.

Or should it be:
1.  A capacitor connecting the wire from the Ignitech terminal 15 to the green wire to the tach.
2.  A resistor placed on the green tach wire (after the capacitor) and leading to ground.


Re the need to open the instrument panel, my trip knob is seized (the trip counter still works, but I can't reset it), so does it just pull off?

 

[Rob]

Just to be clear, if you have used the Ignitech terminal 15 then you won't need the DMC filter. It's purpose is to remove the standing voltage from the feed to the rev counter. On the Ignitech, term 15 just outputs clean pulses with no standing voltage.

The trip reset knob is a push fit. However, it can be a pig to pull off. The shaft can rust.

Pulling the needle off the revcounter is also tight,

 

[Dellortoman]

I queried Ignitech a couple of years ago about the tacho output at pin 15. The reason I asked is that I had one of their TCIP4 units that wouldn't drive a tacho, and I wanted to know what kind of signal I was looking for to measure it. They said it's a 0-12V square wave with 50% on cycle. So a DC voltmeter should show a 6V RMS voltage when the engine is running, and 0 or 12V when the unit is energised with the engine not running, depending where in the cycle it stopped. The unit I was testing had no voltage at any time, so there was a fault at pin 15

They offered to replace the unit, but we had another way to drive the tacho, so it wasn't necessary. The unit worked fine otherwise.

 

[tom3c75]

I've now opened the rev counter, and one of the weights, the smallest one, had indeed fallen off.

However, it seems that someone's already been at the weights.   
One of the weights, a biggish one approx 5mm wide, has been crudely secured with some sort of epoxy, as can be seen in the pic.

So, there are three weights, and I was expecting to find only two.
Should there be three weights, or only two?

I guess I can put it back together and see what happens, but I'd appreciate some guidance before I do so.

Tom

 

[Rob]

Good heavens - bit of a mess in there Tom!

I'm not an expert on the working of the mechanism, but found on mine that replacing the missing weight like-for-like  (as far as possible in estimating the size) with a non-magnetic sliver of lead and re-securing the other two with a squash of needle nose pliers did the trick.  I would have thought that lump of epoxy might be a step too far and upset calibration (such as it is).

 

[Andy]

Hi Tom, there is also a tiny counterweight on the underside of the indicating needle, at the short end. Mine had come unstuck and I had to glue it back in. It didn?t fall right out but was rubbing on the face.
Probably an extremely unusual thing to happen but if you?ve pulled it apart that far...

 

[tom3c75]

Well, I secured the fallen weeny weight back in place, and Dremeled most of the messy epoxy from the large weight.    Also, the gear on the trip reset shaft was misaligned with the matching gear that drives the trip meter, so I sorted that out as well.

The result of this is that I now have a rev counter that works, sort of, and am able to reset the previously stuck trip meter.  The rev counter needle is still a little wavy davey at some points, yet is steady at other times.   

I'm tempted to try and improve things, esp. since I now have the removal of the instrument cluster down to a fine art, takes me approx. 15 mins in all.    Just not sure what to change, though. 

I think I lost a little material on the small weight when I put it back in place, so I could add a bit there.  And I'm not sure whether the biggest weight (the messy one) is original.  It is so much bigger than the other two, about 5mm in diameter and about 6 or 7 mm long.  Seems excessively large compared to the two smaller weights.  Looks almost as if someone had chopped off a piece of lead from a fishing sinker!  So, I could try trimming it own a little. 

However, since it will all  be a bit hit and miss, I'll probably leave things as they are.

Andy, yes, that half moon counter weight under the needle mounting point had indeed fallen off. 
I did not have a clue where it came from, so decided to remove the speedo needle and dial to check if it used something similar, so that I could take my cue from there.  My problem was solved when I saw that the underside of the speedo needle had exactly the same weight.  So, tacho needle weight now glued back in place.

Thanks for all your inputs.

Tom

 

[Rob]

Is the rev counter still being fed from the HT coil/BTZ box (per the original wiring), or are you using the Ignitech output?

 

[tom3c75]

The feed is from the Ignitech box.

I've read somewhere that voltage from other sources in the proximity of the rev counter feed wire could affect the signal.    The Ignitech-rev counter wire runs along the frame tube close to the ignition coils. Perhaps this is affecting the signal?

 

[Rob]

Yep, a possibility but I haven't experienced it. You can use the TCIP4 software to drive the revcounter without the engine running to verify absence of interference.

 

[tom3c75]

Well, I eventually gave up on the Veglia and have now fitted a stepper motor replacement.
The new unit included a switch to select the number of cylinders, so the set up was straightforward.
I calibrated the unit using the Test and Correction functions in the Ignitech software.
The rev counter is now rock steady and reads correctly throughout the rev range.
The indicated revs correlate perfectly with the revs/speed table that is listed in JLO's Laverdamania site.
Slowly, but surely, the silver beast's foibles are being sorted out.

 

[piranha-bro2]

What's a stepper motor? A completely new tacho? Sorry for my ignorance.

 

[tom3c75]

From Wikipedia:

"A stepper motor, also known as step motor or stepping motor, is a brushless DC electric motor that divides a full rotation into a number of equal steps." and "Brushed DC motors rotate continuously when DC voltage is applied to their terminals. The stepper motor is known for its property of converting a train of input pulses (typically square waves) into a precisely defined increment in the shaft’s rotational position. Each pulse rotates the shaft through a fixed angle."

In reality, what I fitted was a relatively inexpensive 52mm generic tachometer with stepper motor internals.
The Ignitech rev counter feed is square wave, so the combination was a happy marriage. Hope it lasts!

The small size of the new unit fitted into the same space as the old Veglia "motor", thus allowing retention of the original rev counter face. By using a small piece of electronic matrix board and soldering the new wiring to the copper tongues on the board, I even managed to reuse the paper thin plastic Veglia power feed and its retaining clip.

 

[arancia]

What you have done to find such an item could be of great value for those among us also suffering from the RGS tacho swinging needle syndrome, would you be so kind as to share the specifics of the "relatively inexpensive 52mm generic tachometer with stepper motor internals" so we can benefit from your research please? Who supplies these, part number, etc? Is this a task for us amateur electronically and mechanically skilled enthusiasts?
I've bought a couple of simple and cheap Chinese GPS speedo and tacho units through eBay with the idea to retrofit them so they look reasonably original but have been pleasantly surprised at how good they look as supplied and am making brackets and housings to put them onto Breganze 750s. I have an RGS with original ignition but wildy erratic tacho so very interested in cost effective alternatives while retaining reasonably original appearance.

 

[piranha-bro2]

Mille grazie for the explanation, Tom. Very simple to understand. I'm in the process of repurposing a ZXR250 Kwaka elec tacho for the SFQ at the mo, and am hoping the Ignitech feed and the tacho speak the same lingo, so to speak. One thing I want to do is make the tacho read at double ZXR speed (so my 8,000 will = its 16,000) by setting it inside the Ignitech box. I'll need to fit a new face or alter the existing one ... unless I want to divide by half in my head whenever I look at it! Hoping I can remove the black Kwaka bezel and source a face without drama.

GPS speedo is a really good match to the Kwaka, same dia and black face. My mounting system, on 3 x M5 male-female rubber silent blocks.

 

[tom3c75]

OK, so here is some information about the unit that I used, as well some detail regarding its fitment, this to give you a sense of the effort involved.

Sourcing information

The unit I bought was listed and ordered through a South Africa web site (www.bidorbuy.co.za). I believe that the unit was supplied by a local, up country vendor (www.autostyle.co.za).

The actual unit is listed on the Autostyle website under the following URL: https://www.autostyle.co.za/product/autogauge-tacho-smoke/

The tachometer is 52mm in diameter, is for 12 volt negative grounded vehicles, reads up to 10,000 rpm over a 270 degree display, and includes a selection switch for the number of cylinders. The product leaflet states that the unit is controlled by a stepper motor.

The price was 550 ZAR, including delivery to my door. That’s about 40 US dollars in real money. It’s not clear from the website whether Autostyle ships overseas but, if they do, then shipping may increase the cost.

The actual unit is made in Taiwan. The only code available is on the barcode sticker. It is: 52ASMTASWL-270. I can’t say whether this code originates from the manufacturer, or from the local vendor.

Pics are attached of the packaging and the info on the underside of the unit.

What was in the package?

A tachometer.
A wiring harness (4 wires) with a connector that slots into the unit’s underside.
A simple metal mounting bracket.
Two pillar bolts, nuts and washers.
One page of installation instructions. (Image attached)

Initial testing

I tested the unit in two modes. Firstly by connecting the green (tacho input) wire directly to the ND ignition coil (negative terminal, black wire), and then to the Ignitech tacho feed. The unit seemed to function identically in each mode.

What I did find, was that the dial was always illuminated when the unit was under power. The unit makes provision for a connection, via an orange wire, to the headlight wiring, and the instructions refer to ‘dimming’ facility. However, I could not get this function to work, and have therefore not connected this wire on the RGS. The lighting is via a tiny LED, which is not accessible.

Fitting the unit in the Veglia instrument pod

Some modification to the new tachometer was required.

The tacho recess in the Veglia is too small to accommodate the 52mm body of the new tach. This necessitated the removal of the plastic housing of the new tach, easily done by levering off the thin aluminium beading that secures the dial lens to the body.

This done, a second issue (the first being the permanent lighting) became evident. I could not pull off the dial pointer from the shaft of the new tach. The plastic pointer was not secured to the tach shaft via a steel needle, as is done on the Veglia unit, but was cemented onto the 4mm shaft. I had to cut off the pointer with a Dremel and fit my own needle to the remaining portion of the shaft. Fortunately the 4mm shaft already had a tiny hole in the centre, which aided the needle fitment. The Veglia uses a .9mm needle, so I used the shank of a .9mm drill bit, which I cut to length and cemented into place once I had spaced the body of the new tach to match the height of the Veglia tach facia.

The new tach body was secured to the bottom of the Veglia housing via the two pillar bolts on the underside of the new unit. The two holes drilled in the Veglia unit were positioned so as not to obstruct refitment of the male wiring connector at the back of the Veglia housing. I also added some rubber spacers to aid stability and to insulate the unit from vibration, although this was probably unnecessary.

Wiring

As mentioned elsewhere, I soldered the wires of the new unit to an electronic matrix board (see pic), thereby simulating the wiring terminals on the Veglia tach (pic attached). This enabled enable reuse of the special Veglia wiring sheet and securing clip (pics attached), all of which obviated the messy business of splicing the new wires into the existing wiring harness. The attached pic shows how the Veglia wiring was matched to the wires on the new unit.

The matrix board itself was secured to the underside of the Veglia dial facia via the two screws that previously attached the facia to the top of the old Veglia tach body.

I also used rubber spacers, positioned to allow routing of the new wiring, fitment of the Veglia wiring securing clip, and to space the Veglia dial facia to allow fitment of the tacho dial pointer. The attached pic illustrates how I mounted the new tach body, the matrix board, and the Veglia facia.

Calibration

The Ignitech ignition software enabled accurate calibration of the new tach. Other than confirming that the new unit functioned when connected directly to an ignition coil, I cannot tell how accurate the readings were. However, the Veglia tach wiring connected via a matrix board can be used together with the old ignition.

Finally

Overall, I’d say that fitting the new unit was straightforward, but finicky. Other than the shaft and needle issue, the effort was as expected. I reckon that you’ll encounter the same sort of wiring and mounting problems regardless of which generic unit is used to replace the old Veglia.

Lastly, I have no special knowledge of these matter. What I know is derived from my experience of years of motorcycle ownership and maintenance. And my electrical knowledge is almost non-existent.

Hope this all helps, rather than confuses.

Tom