tach drive housing types

[machten]

I see yours is one where the cable drive exits 'upstairs', so to speak. Is it a CEV unit, do you know

Hi Craig, That one is running the white face Veglia tacho.

For Smiths gauges on my '74 450 MK3....the tacho drive is as per the integrated cover you have posted..(apologies for being upside down)

IMG_0310 (1024x768).jpg

Nice pictorial summary BTW. Thanks!

regards,

Kev

[Ventodue]

The rather out of focus photo I posted of an integrated tacho drive is a different casting to your photo. There is no grooved edge on my tacho drive, as there is on yours.

Ah ha! Got it! Ta. (Sharp eyes there, Jon ... ).

I don't have any of the Spanish VDO tacho drives to photograph, but I have seen them in the past. If anyone has one they want to sell or exchange, I'm always interested.

Yeah, one of them would be good, eh?

[Ventodue]

I have a bronze drive, “Smiths” type as Eldert suggested, but I don’t know the year. <snip>

Good stuff, Brian - thanks.

The only machine I have seen with the Smith type bronze drive was a 175 Sport, with DUCATII MECCANICA 175 SPORT cast “into” the cover. I would guess at 1958/9.

Like this? This comes from Barry Jones site*, btw. These seem to have been an option, rather than standard fit ex-factory. The period photos that I can find show the F3, and possibly the Grand Sport, coming with tachos originally. But not the Sport. But please say if you know different ...



* http://www.classicducati.com/index.php? ... ductId=311

[Ventodue]

That one is running the white face Veglia tacho.

Ta Kev. Hmmm ... sorry, I wasn't clear enuf . Apologies.

Have a look at the photo below. On what I'm calling the CEV drives, you can see 'CEV' stamped in the end cap. A further characteristic - yours now being Araldite over - is that they also seem to have some light knurling where shown.

Nice pictorial summary BTW. Thanks!

No worries. However, it seems I already need to update it!
(Lawd knows why the design dept at Ducati seem to have spent so much time/effort on resolving this relatively simple task ... )

[double diamond]

The brass drive/ smooth cover (on the left in Eldert’s pic) are Veglia units installed on USA market Diana Mk III, the later Mk3 and included in the race kit for the N/C Scrambler. These were used in combination with the white face Veglia tachs. The tapped hole on the bottom of the drive was originally a zerk fitting to grease the drive. But there was no seal or o-ring on the drive gear and the oil flinger that is part of the drive arrangement was often not replaced so oil made its way into the drive. I’ve been told that the cable would then pump oil up into the tach and fill it with oil! So the practice of fitting a drain in place of the zerk fitting came about. Matt

[DBDBrian]

Hi Craig, Yes that's it. I presume the one's Barry has are replicas, as indeed the one I saw may well have been? My mate had a 175 Sport in the early sixties, if my memory serves correct it was a 1958, it didn't have a tach.

Brian

[450jupiter]

Thanks for all the great posts. I finally put the attached engraved cover with cast drive on my '69 450 scrambler (see picture). For what it's worth, another different looking cover sold on ebay. I am attaching a picture. It has raised letters but looks very different than the other raised letter version. No "Made in Italy".

[machten]

In answer to the earlier query, my 1958 175 Sport (which is unmolested) has no tacho. Could have been an option, though...I don't know.

Capture.PNG

A further characteristic - yours now being Araldite over - is that they also seem to have some light knurling where shown.

I think your onto it, Craig. Yes, my 68 M3D has those knurlings..


regards,

Kev

[Rick]

I can add some more information and confusion to the Smiths tach drive.
The 1962 Scrambler parts catalog- noted as 'U.S.A. Model'- shows the Smiths drive and a plain, smooth cover:

1962 SCR head.jpg

The 'Angle dive, ratio1/2 Smiths (on application)' was also used on the Diana first MK3 about the same time, so I think the Smiths drive can be considered the first unit used in production models.
I have a complete Smiths drive and a drive without the output shaft or the threaded nose that supports it. The problem is, it turns the wrong way. This photo is of 2 drives, a Smiths and a later model, and the output(cable) shafts turn opposite directions with the same input(camshaft) rotation:

tach gearboxes.jpg

This is a photo of the partial drive that shows it has a right hand worm, and 2 left hand worms, as used in the other drives.

smiths shaft.jpg

The mystery is the gearbox from DBDBrian, that has a left hand worm, which would turn the output shaft the right direction.
So, to me, the Smiths drive would need to have it's output shaft flipped end for end, and the drive rotated so the output shaft would be on top of the input worm. Or, fit parts from a left hand drive into the Smiths housing.
I called a guy I know who has a Smiths drive, and over the phone determined that his would also turn the wrong way- he's never used it.
So- has anyone used a Smiths drive?
DBDBrian- did you change the shafts and gears in your drive?
Rick

[thebossdj]

Here are my tach drives. Also the mounts. Jumping in the chat I remember reading something that some of the cables have holes in the bases that allow the oil to drain because the odd time oil would work all the way up to the tach.