Gitane 1980s frameset - French or Swiss BB?

[garethrl]

Hi folks,
I'm talking to another forum member about a nice 1980s era Gitane frame in Vitus 181 tubing and finished in the pro-team shade of blue. We're having trouble removing the drive-side crank from the spindle, the self-extracting bolt is seized and isn't budging. So I tried to dissemble the BB and get the crank off he frame that way.

The NDS assembly came out easily enough but I'm stuck on the fixed cup. The adjustable cup is marked " 35 x 1 " which means that it's either French or Swiss threaded - but the fixed cup is threaded in the opposite sense in either case: right threaded for French, left for Swiss.

I would expect that it's a French thread, but I know that for example Motobecane switched from French to Swiss during the 80s. Does anyone know whether Gitane used Swiss threading at any stage?

Cheers,
Gareth.

 

[PerB]

Re:

Hi
A friends late seventies low to mid Gitane has French BB wile mine 1982 Gitane Olympic (the top model) is with English BS (ISO) BB threads. I have never seen Swiss treads on any bikes.

 

[Nob]

What is a Swiss thread.........never heard of it unless it’s from the 19th Century

 

[garethrl]

Re:

Swiss thread is 35 x 1, the same as French thread. The difference is that the fixed cup is left-hand threaded as opposed to right-hand threaded for a French BB. Some French builders switched from French BB threading to Swiss threading so as to work around the maintenance problems often encountered with French (and Italian, for that matter) BBs.

As ever, Sheldon knows best

https://www.sheldonbrown.com/cribsheet- ... ckets.html

Cheers,
Gareth.

 

[garethrl]

Re: Re:

Hi Per,
I've also never seen a bike with Swiss threading. I was certain that the Gitane would be French threaded, until I read about Motobecane switching to Swiss threading in the 1980s.

I still expect that the Gitane will turn out to be French threaded, but I'm not confident of getting the drive side crank out, and shifting the fixed cup in either direction is proving very tricky with the crank in place.

Cheers,
Gareth.

Hi
A friends late seventies low to mid Gitane has French BB wile mine 1982 Gitane Olympic (the top model) is with English BS (ISO) BB threads. I have never seen Swiss treads on any bikes.