Tacho cable and tachometer won't connect

Status
Not open for further replies.
Bigbossmonty

Bigbossmonty

Joined
Jan 19, 2012
Messages
22
Country flag
Hi lads below are photos of the bottom of the tacho and the end of the new cable.The tacho needle was flickering upon inspection the old cable was not driving the tacho!After fitting the new cable everything is fine up to the end of the new cable rotating freely but it won't fit in to the tacho . It looks like the old cable has broken in the head .Sorry about the strippy y photo it was the lighting!I think the part of the old cable is inside as there is very little space for the new one infact I cannot screw the cable to the head! Your thoughts much appreciated cheers BBM
Tacho cable and tachometer won't connect


Tacho cable and tachometer won't connect
 
The inner circle you can see is only 1mm-2mm down below the threaded part of the clock, it then has a square blind hole again the same 2mm deep. That's why I think it has sheared off that point. I have searched and seen cables with a sliding brass bush so I might be wrong but the inner circle could be the bush with remained of cable in it.
It all rotates freely but would be a b*gger to get out
Cheers
Bbm
 
That silvery shiny section of the inner cable should fit inside the speedo head. When you took the old speedo cable off, you should have noticed if the end had come off or not. From what you describe that's what has happened and you will have to remove the broken section. I understand there are 2 types of speedo and the length of that shiny section is different. If too long, it will jam your speedo, so when you button up the top end, turn the bottom end by had to check if the cable turns easily and the speedo works BEFORE you fit the bottom end to the speedo drive.

Dereck.
 
Bigbossmonty said:
The inner circle you can see is only 1mm-2mm down below the threaded part of the clock, it then has a square blind hole again the same 2mm deep.
Click to expand...

Total depth should be about 15mm.
 
Maybe you can lever the broken piece out with 2 Exacto knives if not too deep. Was also thinking maybe a magnet could pull it out - one of the neodymium coin sized magnets. These are incredibly strong and hopefully the drive fitting would be far enough away from the tach innards so the magnet does not affect them. Or possibly glue (JB Weld) a small piece of wire to the broken piece - very carefully :( .

Russ
 
Hi Russ and Lab,

The 15mm is about right compared to brass section, it was thinking of JB weld or epoxy, emailed Gagg's they say as it's a veglia type they might not be able to remove broken section as they are manufactured as a complete unit internally as opposed to Smiths type, if they can remove it fine it will be cheaper than £120 to replace the internal unit affected.

Cheers
BBM
 
Re: Tacho cable and tachometer won't connect UPDATE

Hi,
Gagg's must been on phone after several hrs could not remove offending item so now getting replacement internal section should note this is a veglia make not Smiths so different inside
Cheers
BBM
 
Veglia and Lucas use different cables, one will NOT fit on the other. Veglia uses a metric thread while Lucas, obviously doesn't. :mrgreen:
 
Veglia and Lucas use different cables, one will NOT fit on the other.
Click to expand...

Not on a Norton factory fitted Veglia, cable for both speedo and tacho is the same for Smiths and Veglia as are the rear wheel gearbox and tacho drive.
 
Jagbruno said:
Veglia and Lucas use different cables, one will NOT fit on the other. Veglia uses a metric thread while Lucas, obviously doesn't. :mrgreen:
Click to expand...

The standard "Lucas" :? (I believe you mean Smiths?) cable/instrument thread was 12mm x 1.0mm and had been for many years (a legacy carried over from the Jaeger Chronometric era see link, below) consequently, Veglia instruments intended to be used in place of Smiths have the same thread. Both Smiths and Veglia instruments were fitted (in pairs) from 1973-on and only one speedo and one tach. cable is listed for both makes.

http://velobanjogent.blogspot.co.uk/200 ... nd_21.html

Veglia and Smiths speedo drive gearboxes do have different threads, but as Veglia drives were not used on Nortons (as they were on late Triumph twins) it's not exactly relevant.
 
Yes, Smiths obviously.

However, I am positive the Smiths and Veglia cables are indeed different and not compatible. I do know because I have 2 sets of gauges on my Norton racer, and when I switch between the Veglia green dot and the chronometrics, I have to switch the cables as well.

:mrgreen:
 
Jagbruno said:
However, I am positive the Smiths and Veglia cables are indeed different and not compatible. I do know because I have 2 sets of gauges on my Norton racer, and when I switch between the Veglia green dot and the chronometrics, I have to switch the cables as well.
Click to expand...

Yes, but that's because you are swapping between Veglias and Chronometrics which have a different cable connection to *magnetic*, however, the thread should be the same.
Tacho cable and tachometer won't connect
 
Below, Left, '73-'74 green globe Veglia. Centre, '71 -'74 green globe Smiths. Right, '69 green blob Smiths. All M12 x 1.0 thread.

Tacho cable and tachometer won't connect


'68 - '69 green blob instruments below, right, are 7/16" drive depth, '70-on, left, are 9/16" (Smiths and Veglia).

Tacho cable and tachometer won't connect
 
Status
Not open for further replies.

Similar threads

O
  • Locked
75 Commando tacho cable
Replies
2
Views
1,255
Owen Peake
O
B
  • Locked
Tacho Cable
Replies
3
Views
885
hewhoistoolazytologin
H
T
  • Locked
Tacho Cable replacement
Replies
12
Views
3,468
TT
T
Back
Top