I recently picked up a UniVega Viva Sport on CL for $50. It's a complete bike, hardly any rust and was the perfect candidate to tear down and rebuild. I've learned a lot about older road bikes in this venture but, I can't find much information on the UniVega's. I know what Wikipedia has told me and various other tidbits from a local bike shop and around the web.

I've read something about the head tube of French bicycles being smaller than that of Japanese bikes. But, I don't believe my UniVega falls in that category because of the "Made in Japan" sticker on the bike.

I made the assumption after reading countless hours on the net that it was 1". Well, I was wrong. I ordered a 1" to 1 1/8" quill stem adapter and it doesn't fit in the head tube.

Could anyone tell me the size of the head tube?