electronic rev counter 350 Sport...

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Matt Hale
Posts: 75
Joined: 08 Oct 2020 10:00
Location: London

electronic rev counter 350 Sport...

Post by Matt Hale »

Hi All- my old electronic rev counter is completely recked- it started with circuit board failure then I tried to fix it and ruined the whole thing !

Do any of you have a spare or know where I can get a replacement? I have been looking for ages...I might be ok with a non Morini one if it was the same OD size- any recommendations? I did find a non Morini Veglia second hand but it only comes alive if I rev very high...maybe there's something I can do about that?
Many thanks in advance for any help!
Matt
350 Sport 1979 electric start model (missing)
Curry yellow tank etc paint work, navy blue frame, silver wheels.
MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: electronic rev counter 350 Sport...

Post by MickeyMoto »

Hen's teeth, I'd say.

You can swap for a mechanical one, but the clock is completely different.

I think some early Guzzis had the Vagueliar electronic tachos.
Mepstein
Posts: 147
Joined: 27 Apr 2016 02:38
Location: Newark, Delaware
Location: Newark, Delaware, USA

Re: electronic rev counter 350 Sport...

Post by Mepstein »

A friend of mine buys a modern generic tach and moves the new "guts" into the old housing with the original face and needle. He's done a couple and it seems to work well. Not much to loose trying if your old one is non functional.
Matt Hale
Posts: 75
Joined: 08 Oct 2020 10:00
Location: London

Re: electronic rev counter 350 Sport...

Post by Matt Hale »

Hi -Thanks for these possibilities- both good- how do you change to mechanical?- Would I need to buy a new engine case or something? There are lots of mechanical Kanguro Tachos available not sure how to use them...mecahnical more reliable and less fragile then electronic probably?
thanks again
Matt
350 Sport 1979 electric start model (missing)
Curry yellow tank etc paint work, navy blue frame, silver wheels.
MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: electronic rev counter 350 Sport...

Post by MickeyMoto »

Hi Matt,

You need a new cover eg https://www.ebay.co.uk/itm/273928922688 ... SwTFRdKy9E (but not at that price!)

the 90 degree bend thing and a nut with a square to go on to the camshaft.

Or

https://www.mdinaitalia.co.uk/M460306U.html
-------------------------------------------------------

Mike.
BumbleBee
Posts: 140
Joined: 13 Jun 2017 21:10
Location: Reading

Re: electronic rev counter 350 Sport...

Post by BumbleBee »

Just a thought. The model of electronic tacho on Morinis are very specific to Morinis because of the firing interval, if yours is totally wrecked it may be best /easiest to have it professionally repaired. Other people have had top quality service from professional repairers such as Peter Bond ( guageman1@gmail.com ) He's probably the best (and costs reflect this) but versus the cost of finding a mechanical one, and cable, and camshaft end drive bits and other small bits and whether it's face will match the speedo...
If it's not totally wrecked that's another matter, but if you reckon it is.

G&A
MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: electronic rev counter 350 Sport...

Post by MickeyMoto »

BumbleBee wrote: 26 Oct 2021 10:33 Just a thought. The model of electronic tacho on Morinis are very specific to Morinis because of the firing interval,

G&A
That's interesting. I always thought that the transducer would control the tacho. Not sure if this is every stroke or every other stroke on that particular cylinder.

I would be interested to see how it works. It can't be a difficult circuit, bearing in mind it was designed in the 70s. No microchips! :)

Mike.
lemans
Posts: 63
Joined: 01 Oct 2017 18:52
Location: Heino

Re: electronic rev counter 350 Sport...

Post by lemans »

BumbleBee wrote: 26 Oct 2021 10:33 Just a thought. The model of electronic tacho on Morinis are very specific to Morinis because of the firing interval,
G&A
no, not really.
there one grey wire from a transducer to the tacho, so its one pulse every 720 degrees, 2 crankshaft rotations
BumbleBee
Posts: 140
Joined: 13 Jun 2017 21:10
Location: Reading

Re: electronic rev counter 350 Sport...

Post by BumbleBee »

Mike,
Someone was ahead of their time, there's definitely something like a chip in there :-)
About the pulses. To get the right rpm displayed, from the available signal., it's not that simple, although we all wish it was. It's maybe not about the firing interval it's maybe something else.
Heehee don't ask us any more details we'll need to go and consult a grown up :-)

G&A
MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: electronic rev counter 350 Sport...

Post by MickeyMoto »

BumbleBee wrote: 26 Oct 2021 16:24 Mike,
Someone was ahead of their time, there's definitely something like a chip in there :-)
About the pulses. To get the right rpm displayed, from the available signal., it's not that simple, although we all wish it was. It's maybe not about the firing interval it's maybe something else.
Heehee don't ask us any more details we'll need to go and consult a grown up :-)

G&A
Does it use PFM technology?
BumbleBee
Posts: 140
Joined: 13 Jun 2017 21:10
Location: Reading

Re: electronic rev counter 350 Sport...

Post by BumbleBee »

Oh purely :-D
Isn't that how all manufacturers explain their kit :-D

G&A
User avatar
Ming
Posts: 798
Joined: 01 Aug 2014 16:32
Location: France
Location: Central France

Re: electronic rev counter 350 Sport...

Post by Ming »

I think somewhere in my archive I have a circuit for the driver - the tachometer is just a meter I’ll see if I can find it.
MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: electronic rev counter 350 Sport...

Post by MickeyMoto »

Found this... May be worth checking it isn't a simple mechanical fault first.

https://wildguzzi.com/forum/index.php?topic=86108.0
huub
Posts: 194
Joined: 24 Jul 2006 15:11

Re: electronic rev counter 350 Sport...

Post by huub »

i had a friend fit another printed circuit board in a morini rev counter , because he could not find the original semiconductor so could not repair the original PCB.
apparently it is a simple device converting pulses to a raising voltage.
but the internals of any rev counter ( for a single ) should work
lemans
Posts: 63
Joined: 01 Oct 2017 18:52
Location: Heino

Re: electronic rev counter 350 Sport...

Post by lemans »

http://www.loutrel.org/Veglia.html

schematics of the rev-counter
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