I have what I think is a 1981 Motobecane Jubile Sport ... I say I think because the spelling or miss-spelling of 'Jubile' fits that year gap. Anyway, it's a french tubed vitus frame with Japanese components. Thus, the bottom bracket is english threaded.

The headset is branded 'Motobecane' and is not very high-end. It's constantly coming loose and I'd like to upgrade it. The question is ... JIS,ISO,or French? I have no clue which it is.

Any suggestions for quickly identifying the style without per-purchasing a new headset?

Pics: https://gallery.me.com/stephen.ogden#...&bgcolor=white

Ignore the valve length and I've since made some other changes.

I have an early eighties Motobécane Nomad II that had a bent frame set. I saved the headset from the bicycle, which had an English threaded BB, but the headset is French (25mm OD & 22mm ID). I might add that the set is close to identical to the one fitted to my 1978 Motobécane Grand Jubileé...


I hope that is a help

The only way to know for sure is measure the stem.... If it's 22mm it's french, if it's 22.2mm it's either ISO or JIS, and at that point you need to measure the crown race I.D. 26.4 is ISO and 27.0mm is JIS.

Thanks. Very helpful. And my headset looks identical to your grand Jubilee's. Great bike by the way.

I love my Motobecane despite its general lack of prestige. I like that it's got one foot in France and another in Japan and that it looks like a Bianchi but most certainly isn't.

Just curious because I just picked up a 1980 Grand Jubile - how do you know that the BB is English threaded and not Swiss (and how does one tell the difference)?

1981 should have Swiss bb. It will be marked. My 1979 and 1982 Motobecanes both have Swiss bb and French HSs.

Franco-Japanaise love in the bluegrass state. Love it.



Since you're going to remove it anyway, measure the crown race and go from there. Dollars to doughnuts that it's French given the year. Your best bet is vintage Stronglight or Velo Orange.

When I re-packed the BB, it was labeled "Sakae" ... looking at it again, it also says "Japan - SI" .... which could well stand for 'Swiss' or perhaps 'sports illustrated' but I'd bet the former. So, the Japanese threaded a Swiss BB cup for installation on a French bike sold to the US market. Then called it Jubile. It originally had the notorious Shimano FB halfsy freewheel/cassette hub thing (to remove it is to destroy it ... which I did). What a masterpiece of engineering that was. The SunTour BL (blue line) GT in the black version is also humorous to me. That's why I love this bike. A rolling velo faux pas.

I measured the stem and it's 22. So Porter Wagoner tips his hat.

Bonus points for correct spelling of Wagoner. Double bonus if you didn't have to Google it.

This color kills celeste.



The BL derailleur obviously borrowed heavily from the first generation Cyclone GT; a favorite of many.

Twas Googled. I was looking to see if he ever wore a hat ... with that head of hair, I don't think he did.