Identify my Motobécane racing bike I bought a Motobécane last year (pics below), and now that the bottom bracket is broken, I really need to know the model of the bike, to help me change that piece.

It would also be helpful if someone could redirect me to the Motobécane catalogs of the years 82, 83, I can't find them, and I suspect my bike is from this period.

Technical specifications:


frame color: green and black (How customizable was that? I think they didn't sell the same colors each year)
frame: tubing inexternal 707, "trainer" (I don't find the appropriate info about it)
brakes: Weinmann
derailleur: Sachs - Huret. 12 gears
Wheel: Maillard
Bottom Crank: ?? width of the shell: 74mm. From this page http://sheldonbrown.com/vrbn-g-n.html, the old french ones have special dimensions. Also on Motobécane, they are swiss type (left-threaded). I don't know if this is a cotterless one, shimano octalink, or if I can put something more standard?


[EDIT: As suggested by @Blam, I took the bottom bracket out.
First mistake: shell width doesn't correspond to the red line on the pic, but less, so width should be 68mm, I'll double check on the bike.
The Brand is Stronglight, french brand, but the threading is the normal one (left-threaded on the right side, and right-threaded on the left side).
The axle is 120mm long, tapered square. Like this model: http://www.ebay.com/itm/VP-Components-Bottom-Bracket-120mm-Square-Taper-Unsealed-Bike-NEW-/311359596201?pt=LH_DefaultDomain_0&amp;hash=item487e7a66a9

But anyway, I'm still interested in knowing the model of this bike, and/or finding the Motobécane catalogues of years 1982-83]

Important Note: The rear wheel is not the original (was broken). I also changed the part of the crank where I put the feet when I bought it (maybe I shouldn't have...). 

Sorry if it looks quite dirty, I didn't have time to clean.

Pics:
I don't know the exact model (probably is Trainer as shown on the top tube decal) but it was likely built sometime right around 1984, most likely 1984-1986 judging by the parts. The brand was known as Motobecane for most of their history. They went bankrupt in 1981 and were bought by the Japanese (Yamaha or Suzuki, I forget which) who relaunched the brand in 1984 as MBK (like many other French bike companies, they made more than just bikes - see also Peugeot). 

The other giveaway is the Sachs-Huret rear derailleur. Sachs and Huret were separate companies - one German, one French - prior to 1980. In 1987 they introduced an indexing system to keep up with SIS which had come out the year prior from Shimano and was a massive hit. In the late 90s the combined company was bought by the American SRAM company. The shift levers look to be friction so that dates them to after the Sachs/Huret merger but before the advent of indexed shifting. 

It is an entry level bike. The big giveaway is the tubing decal which says "Hi Tensile". Hi Tensile (or Hi-Ten) is the lowest grade of tubing used in bikes. Pretty much the same stuff used in Huffy and other department store bikes. That said, not all Hi-Ten is created equal and there are actually some Hi-Ten frames that ride quite nicely even if it's far from being the lightest tubing. Nicer level Motobecanes of the era would have been made using Reynolds 531 or various grades of Vitus steel tubing. 

As you've probably discovered by now the bottom bracket is a regular taper with English threads. Most French bike companies stopped using French threads in the late 70s/early 80s much to the relief of bike shop mechanics everywhere!