Some bikes with 25mm French-threaded steerers do take 22.2 mm stems, but I have never been sure whether that was because of tolerances in the steerer tube or subsequent reaming or by intent from the factory. I have one such bike and take comfort from the fact that it has a wooden plug up the steerer to reduce the probability of a catastrophic failure. A standard French steerer tube has less wall thickness than a 1" one, and even less with a 22.2 mm hole down the middle.
22.0 mm Cinelli stems appear from time to time on French eBay, but you need to be a bit cautious - one vendor told me a stem was 22.0, but when it arrived I measured it at 22.2. I don't think he was trying to deceive because I asked him the non-leading question of whether it was 22.2 or 22.0. I think there is more chance that the vendor knows what he is talking about if the item description states 22.0.
From: Freek Faro <email@example.com> Subject: Re: [CR] 1981 rare motobecane team champion To: "P.C. Kohler" <firstname.lastname@example.org> Cc: email@example.com Date: Friday, 28 January, 2011, 21:55
Fortunately my '78 Team Champion takes a standard 22.2 mm stem. It does have a French threaded and a Fench threaded headset though.
Freek Faro Rotterdam Netherlands
2011/1/28 P.C. Kohler <firstname.lastname@example.org>
> "I compiled some pictures of Motobecane Team Champions from 1974 through >
> the early 1980s. Note: ONLY 3 OF THE BIKES ARE MINE... The rest I copied
> from the internet."
> Excellent Chas. and thanks, too, for the synopsis of this rather neglected
> but superb model. My '74 Moto Team Champion is one of my alltime favourites
> in ride (she's a 62cm c-c so perhaps another example of big bikes ride
> best?) and eye candy appeal. But I really want one of the early 80s models
> with those delicious late era Spidel components to compliment my '82 Peugeot
> But why, oh, why, was the "Team Champion" called that (always) when it was
> written "Champion Team" on the top tube up until the 1980s? Or is that
> another endearing Gallic inconsistency to go with trying to find 22.0
> Cinelli stems for these machines?
> Peter Kohler
> Washington DC USA