1970’s Italian steel. Can’t find any info about this brand.

Paint is in rough shape but seems like a quality frame.

Radius was one of the brands owned and manufactured by the Rizzato company, which was best known for their Atala brand. The Rizzato origin is confirmed by the serial number format, which is located on the drive side of the upper seat tube and in this case indicates a 1967 model.

Given the era and characteristics, Id' expect Columbus SL or SP tubing, the former which would use a 27.2mm seat post, while the latter would use 27.0mm. The presence of one of these two tubeset can also be confirmed by the presence a Columbus steering column for the fork, with five helical ridges on the inside, at the bottom. If you remove the fork, there should also be the Columbus dove logo stampoed into the outside of the steering column.

Nice acquisition. Enjoy!

I don’t have it yet. Checking it out later today. I’m so glad you provided above info. Yeah, should be fun project.

I have been hanging onto a full Campagnolo Record group from 1966 so this should be a great match.

Now I’m getting somewhere.

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the underside of the shell may exhibit a number 23 in two places

this is the frame's nominal size as measured in inches, measuring c-t-t

another badge owned by Rizzato not shown in the emblem illustration is that of Maino

lug pattern Prugnat 62/d

frame same as that of the Atala model Professional


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That is a lovely frame! Looks like it should clean up well. Looking forward to seeing more of it.

b dub We can compare frames. My 1970 Atala Super Professional is hanging in the basement, devoid of parts.

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one minor feature it does not show is the vee shape at the junction of paint and chrome on the taper tubes

some examples show it and some do not

at first thought it might have to do with model year but seems they went back and forth with regard to this feature...

perhaps our Rizzato experts shall be able to comment

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I picked up the frame today. As known the paint is in rough shape but the frame seems solid.













The period correct Campagnolo Record group I have available to build this frame up with includes a 27.2 seat post but it doesn’t fit. I’ll confirm later that a 27.0 post does fit.

I checked the fork but don’t see the Columbus dove.

There is more clean up to be done but I’m liking the results. I was able to remove 99% of “DIEGO” stick on stickers so far.

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for readers who have not seen one these Rizzatos of this era previously the white paint on the frame ends is indeed from the factory - appreciate it looks peculiar at first glance...


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I’m not touching it😀

I am however removing the white and red reflective strips on the back. This frame clearly has had a live.

Is this bike shop sticker original? Should I leave it alone? Looks more recent.

The cinch slot for the seat post is notably pinched at the top, as if a previous owner used an undersize post. Gently pry the cinch slot open with a large, flat bladed screwdriver, until it is slightly wider at the top than the bottom. Also, make sure there are no burrs or foreign material build-up on the inside of the seat tube. If so, remove with a reamer, hone or emery cloth. Then try your 27.2mm post.

Did you remove the fork? The Columbus dove logo is the outside of the fork's steerer tube, so you have to remove the fork to see it. Sometimes it can be quite faint. You can also verify a Columbus steerer tube by the five helical ridges on the bottom inside of the steerer tube (see attached). On old frames like these, corrosion and dirt build-up can make them hard to see.

I confirmed; after removing the fork I could not find the Columbus dove and no helical ridges.

Also, the seat post size is 26.8.

If the info provided in correct, then it is not a top model with Columbus tubing. It doesn't appear to be Libellula, so it's most likely a Falck tubeset and 2nd from the top of the Lygie line.