n/c bike identification

[ducwiz]

Hi all,

recently a remote friend discovered a n/c single, probably a 125 Sport. The pre-owner claimed 1957 as the year of manufacture. According to a list on bevelheaven.com, the bike should have a frame number like 20xxx. But strangely, 251xxx is stamped into the frame, which seems to identify it as a 100 Sport from the mid-60s.
Any expert here with deeper knowledge of number history?

??? Hans

[Ventodue]

(FWIW)

That's also what Ian Falloon says, Hans - i.e. the 125 Sport had numbers 20xxx. Unfortunately, he doesn't say anything about the numbers for the 100 Sport ...

Ciao

Craig

[gtrench]

Most 1957 Ducs have a bolt on rear frame loop, swoopy passenger peg mounts, and re-enforced single bolt front down tube (single bolt at engine mount plates) among other small details. Perhaps that will help ID the chassis.
-Gabe Trench

[ducwiz]

Thanks guys for your tips, and sorry for my delayed reply.

As the bike has the newer mount plates and a fixed rear frame, it must be newer than '57.
This riddle is still to be solved.


cheers Hans

[gtrench]

Any way of posting a pic of the bike? Also, are there any other numbers than the "250xxxx?" I've seen some Duc 160's running numbers in that neighborhood....externally, then engine looks just like a 125 sport. You can also go off of wheel size, 125 sports had 17's, 160's 16 inch....plus, hub size could narrow down the years. If it is a 125 sport, the early ones (approx pre 61-ish?), had the full size 180mm/160mm hubs like the "bigger" bikes, then in the early sixties they went to the smaller hubs that came on the 160's.
Good luck.
Gabe Trench

[ducwiz]

Gabe,

sorry, the bike is already totally decomposed for restoration. But according to the owner it looked like this one:
http://www.topspeed.com/motorcycles/motorcycle-reviews/ducati/1965-ducati-100-sport-ar129429.html
This bike has no. 25xxxx.

A second 100 Sport with frame no. 25xxxx can be found her: http://bevelheaven.com/data-single.htm

Thanks for the tip about the brake diameters, I'll ask the owner about this detail

cheers Hans

[ajleone]

Hans,
I own the 100 Sport in both sites you listed. I do not believe it is a 1964 as it is advertised. IMHO it is a 1957 or 1958. I am a little confused, the 125 Sport has a different frame than the 100 Sport and also a different gas tank. Given that, I am not sure his 125 can look like a 100 Sport. Ducati also Made the 125 Aurea which is a push rod engine in the same era. Is the bike in question a bevel engine ? 100 or 125 ? Can you get a pick of the gas tank and engine ?
Tony

[ducwiz]

Tony,

thanks for your reply and the info.
Of course the bike in question has a bevel engine. I'll get in contact with the owner and ask him for some photos of tank, engine and maybe frame.

Hans

EDIT The owner measured the brake drums: 180/160, so the bike has to be pre-1961.

to be continued

[ducwiz]

Hi,

finally, the owner sent some photos of the deconstructed bike, as he purchased it.















Maybe, this can to identify the bike.

cheers Hans

[Ventodue]

Hi Hans,

Well, we (now) know it's a 125 not a 100 'cos:

It says so on the cam cover .. and on the tank badge . And the headlamp is gold, not silver. And we know it's a Sport 'cos of the tank shape. So which year?

Thoughts:
a) The rear hoop of the frame (where it goes over the rear mudguard) is continuous. So that would suggest it's not the first version (1957) of the 125 Sport.*

However:
a) The rear light fitting is the type that you see on the first version. And this bike also has the metal tank badge of the first version.
b) As for the smaller brake drums ((158 & 136mm), Mark Poels in 'L'Histoire de Ducati" says these came in with the second version which Ducati announced at the end 1957, i.e. 1958 sales/registration year.

So all a bit confusing. But what if someone has changed the frame, maybe even with a 100 Sport frame? That might explain why the frame numbering sequence (25***) seems to be that of a 100 Sport ...?

Craig

* As already mentioned by Gabe Trench: On the first 125 Sports, the main frame stopped short (as it did on the 125 T). The hoop on the Sport was formed by a piece of bolted-on tubing - see attached photo.