They cannot. The clampon retrofriction has a clamp with a different post diameter (larger IIRC) than the diameter of a Campy brazeon. I think this was true of clampon alloy Simplex Criterium shifters as well. I don't know why this was, but I'm guessing maybe at one time Simplex made shifter brazon fittings that were larger than the Campy fittings, so the post size on the Simplex clamps may have matched such old Simplex brazeon fittings.
The brazeon retrofrictions, at least the ones I've seen, fit Campy brazeon bosses, so the retrofriction brazeon and clampon levers are not interchangeable.
Oddly enough, the clamp for the cheap (and terrible) plastic Simplex Prestige shifter WAS the same size as a Campy brazeon boss, at least in the 70's. This has come in handy as I've been able to convert brazeon retrofrictions to clampon by using Prestige clamps. The clamps are actually pertty nice, although the shifters are crap. I bought a whole bagful of Prestige shifters cheap from Mike Kone years ago, and I've only ever used them for the clamps. I wouldn't dream of actually using the shifters.
Regards,
Jerry Moos
Big Spring, Texas, USA
> From: Emerson Johnston <emerson.johnston@gmail.com>
\r?\n> Subject: [CR] Simplex shifter question
\r?\n> To: classicrendezvous@bikelist.org
\r?\n> Date: Tuesday, June 2, 2009, 5:04 PM
\r?\n> I am 99.99% certain these are RETRO
\r?\n> FRICTION
\r?\n>
\r?\n> The tricky question is
\r?\n> :
\r?\n> Can they be used on standard Campag brazed on bosses
\r?\n>
\r?\n> Maybe yes but probably no!
\r?\n>
\r?\n> All the 70's era levers I have are not Canpag compatible
\r?\n>
\r?\n> Regards
\r?\n>
\r?\n> Emerson Johhnston
\r?\n>
\r?\n> Lurking in Kanata (Ottawa) Ontario Canada