1965 Ducati 250 Mark III - Diana?

[Ventodue]

But with the tanks
- the first series had symmetric undersides (very expensiv if you need one)
- later models have got the asymmetric undersides

Yes, but the modification to the tank was done ONLY to accommodate the larger SSI 29 carb. As you can see from Anthony's photo, this bike has a SSI 27 carb.

So this bike has the right tank for it's carb!

[Moto Chuck]

Interesting frame with the Mark 3 tool box mounting tabs but not the rearset mounts. Still for a 1965 that is probably correct.

Hmmm...

I still lean towards early/mid-1964.

1. The numbers correspond with Ian Falloon's advice.
2. There is blue paint underneath the red over-coats. Blue wasn't used on 1965 Mark 3s. To quote Tom Bailey, talking about the 1965 Mark 3, "We never saw any with that paint scheme".
3. This bike has both a SSI 27 carb and the gas tank that goes with this carb. This is correct for 1964 Mark 3s. In 1965, the larger SSI 29 and its tank were fitted.
4. Even if Mach 1s weren't offically imported into the States, 1965 Mark 3s were fitted with Mach 1 engines. And these engines have Mach 1 engine numbers. This bike doesn't.

Plus:
5. This bike has the lugs for the passenger footrests. Apparently, these disappeared during 1964 - and did not feature on the 1965 bikes.

Thoughts?

I don't recall having seen a narrow case frame made for the street that did not have what you call the passenger footrest lug. All my Monza, Mark 3, and Sebring frames have that lug right above the muffler mount lug. I do have a couple of Scrambler frames that did not have the passenger footrest lug and they also have the unique seat mount that distinguishes them as Scramblers.

[KarstenH]

Hello Anthony,

Ventodue is right - for the SSI-29 the mach1 get a handmade modifikation.

Mach1 for SSI29.JPG

But in the history of the Diana we had two different tanks
early

eraly Diana 62-63.JPG

please note - my tank has an extra mod for an SSI29

and late

late Diana 63-65.JPG

[Ventodue]

Excellent Kirsten - thanks!

I've stuck your two photos next to each other to make the difference more obvious.

[Ventodue]

I don't recall having seen a narrow case frame made for the street that did not have what you call the passenger footrest lug.

Excellent! The mystery gets murkier ....

Well, I've found quite a few examples, either in the form of factory illustrations or photos of actual bikes: 160 Monzas, 250 Scramblers, Mark 3s, Mach 1s ...

Here. for example, is a photo of a Mach 1 taken from Ian Falloon's book - and where he specifically mentions the absence of lugs:


And here are scans of 3 different models, each taken from their respective parts book. Each illustrates a frame denuded of the lugs. And the first two even illustrate how the pegs were intended to be mounted.



So ... dunno! Maybe the lugs were specific to US export bikes? Who knows?

[Moto Chuck]

I don't recall having seen a narrow case frame made for the street that did not have what you call the passenger footrest lug.

Excellent! The mystery gets murkier ....

So ... dunno! Maybe the lugs were specific to US export bikes? Who knows?

Well here is a survey of the contents of my garage. Presumably all brought into the US by Berliner Corp.

1 Mark 3 Has upper lug and rearset lug.

4 Monza-Sebring frames. All have the upper lug.

3 Scrambler frames. Two do not have the upper lug and one does. Interestingly (never noticed before) one frame without the upper lug does not have a battery tray/rear fender mount either.

[Bevel bob]

My UK 67 Mark3 narrow case has the extra pillion rest lugs. Most of these bikes were intended for the USA.

[MrPink]

So much great info

I have just stumbled across this website after searching 1964 Mark III and there is a bike that is very similar. They call it a Type B and it also has the D on the frame tag and identical foot peg lugs.

http://www.ducaticollectors.com/1964-di ... ype-b.html

I wonder if the tank was originally blue and the factory just repainted it red when they shipped it out. I have a 750GT project that has a fibre glass tank in the original black paint with white stripe but also underneath that is a gold metal flake, Hard to see in this picture but

IMG_9485 by pink.anto, on Flickr

[Ventodue]

I have just stumbled across this website after searching 1964 Mark III and there is a bike that is very similar.

Good pick-up, Anthony! Yup, that all makes sense: 179 shipped to the USA in 1964, his number 87982, yours 88162.

It seems likely that the first bikes didn't arrive until late 1964, btw. This would make sense as new models were often (always?) put on the market after the factory went back to work in September. This would also chime with Ian's statement that the homologation document for the 250 GT, the first bike to use the new 5-speed box, wasn't delivered until 13 November 1964.

Also I note that the Cycle World road test appeared in November 1964. It's not unreasonable to suppose that the test was done sometime during the previous month, on a model that was then new to the market.

A late import date, plus its late number, would explain why your bike wasn't registered until the following year.

They call it a Type B ..

That's right. The Type B engines began with the 4-speed 250 engines in 1961. Differences from the Type A engines include longer cam shaft and crankshaft, new crankcases, 4 cooling fins on the head, uneven flywheels, location of swing arm bushes etc.

... and it also has the D on the frame tag

Excellent! But what does it mean?

From what I can work out, the 250 GT was being produced at the same time, using the same frame and therefore the same frame numbering sequence. So maybe the 'D' did, indeed, stand for 'Diana' to differentiate it from the GT? Altho' I can't see any reason why anyone would have particularly wanted to make the differentiation ...

I wonder if the tank was originally blue and the factory just repainted it red when they shipped it out.

I've had exactly the same thought ...

[Rick]

The SSI 27 and 29 are both made from the same casting- the 25mm SSIA through the 30mm SSID are the same physical size, even use the same slides. The 'venturi' bore and the insert in the slide are machined unique for each size, but the overall height, width, depth are the same. The 'A' and 'D' series have different air and fuel passages, but the bodies are more or less the same size.
Rick