spock345

I have an opportunity to pick up a '78 or '79 grand Jubilee bike frame and fork with Vitus tubing for $30 (include downtube shifters and a seatpost). I already have almost all of the right parts to build it up lying around (70's suntour drivetrain, wienmann center pulls, french leather saddle, etc). The only catch is that it is a 56cm frame and my current bike is 57cm, it doesn't seem like much of a difference but I am not sure. Also the headset and bottom bracket feel crunchy when moved, with some small paint chips and worn decals (they are still legible). I can get the parts to fix it at the local bike co-op (they have a bin of french and italian BBs and headsets) for about $20, along with access to all the tools needed. Is it worth the money and effort to build up the frame?

eschlwc

yes, it's worth it. i paid almost $100 for an '80 frameset. i found a donor bike for $75, and had a really nice bike afterwards.

spock345

One thing I am worried about is the possibility of a swiss bottom bracket, which makes finding parts hard. What kind of BB does yours have?

Pawlus

BB in 1980 Jubilee was English thread. It has 126mm rear spacing.

verktyg 

1cm = 10mm = slightly over 3/8" - about this much I----I

French bikes were originally measured from the Center of the BB to the top of the seat tube. The 1978 and 1979 US Motobecane catalogs lists Grand Jubile frames in sizes 21", 23" and 25". These were nominal since the frames were 53.5cm, 56.5cm and 61cm which are center to center measurements.

I can ride most 54cm to 57cm frames. I prefer 55cm or 56cm seat tubes. Contrary to what fit meisters might say, stand over height is my biggest concern. I like to have a comfortable distance between the top tube and my personal region in case I have to dismount in a hurry.

I bought a 1980 Grand Jubile frame that was listed on eBay as 56cm... Well, it's 58cm center to top with a high BB so the stand over height is about a inch too high for comfort. Also, those bikes usually had long top tubes.




Many of those bikes used a Motobecane badged headset made by Stronglight. The top lock nuts were black chrome. They were decent quality.




"Crunchy" can mean a lot of things.... It can mean sand or grit has gotten into the bearings. It's not always as bad as it sounds; depends on how much wear and damage has been done to the bearing races.

In some cases it can just be overtightened bearings. You have to disassemble the BB and headset to diagnose the problem.

As far as threads are concerned, the was not logic to the standards Motobecane used. The BBs could be French or Swiss metric or possibly British threads. British threads were more common in the 1980's.

Headsets are easy to tell because the threads are ether 25mm or 25.4mm (1") diameter.

BB cups may have some markings on them.


verktyg

Chas.

spock345

Well to answer those two questions I could ask the person who has the frame if I could screw a cup off of the BB. Not only to check the internal state but also to see what threading it has. They both felt as if there was sand or grit in the bearings. Then check the stand over height.

bikemig 

I'd buy it even if it had a swiss BB; that's a great bike at a great price particularly given that you have nearly all the parts. You can get swiss cups from IRD for $24: Italian, Swiss and French Conversion BB Cups

You'll need to get a IRD BB as well and those start at $33, QB-55 Quad Bottom Bracket

spock345

Well given that it is a ~$80-$100 investment for the frame and that BB you linked in the worst case scenario, an trashed swiss bottom bracket, I can easily make that money back by selling off some parts I have lying around.

francophile 

If you really need Swiss cups, you'd be shocked at how many members probably have a pair laying around. I have three or four, two with cottered spindles to match, one with non-cottered spindle at least. I'm sure you could beat eBay prices on something closer to period-correct. Really depends on the year.

$30 for a frame/fork/bottom end is a winner any day as long as the frame isn't cracked, dented, damaged, or rusted along the lugs - you don't need to worry so much about the rust, but cracks in aluminum frames is a concern.

spock345

Well I guess I will go look at it again on Monday and probably pick it up, then go down to the bike co-op and start working on it. If the condition of the BB and headset aren't too bad then I can probably have it put together in some form by the end of the day. I will post pictures and such once it is put together.

old's'cool

Sounds like a great find. Go for it!

I agree with Verktyg, my 78 GJ's top tube is noticeably longer those of my other bikes with similar ST dimensions.

stevegreer

Absolutely stunning! Pardon the drool...

eschlwc

^ the bike was one of the nicest and longest (in wheelbase) i've rebuilt.

its length made the 23c tires feel like 28s, and the new brooks like it was already broken in.

it made me a fan of vitus 172.

maybe the perfect machine to take that extended tour.

stevegreer

I have to say that one of the most comfortable saddles I have ever sat my butt in was a Brooks. About 5 years before my father passed away he gave me the '87 Trek in my signature. It had a Brooks saddle, but unfortunately the tip broke off not long after I got the bike and I swapped it out with a brand new Selle Italia Filante. Night and day difference in those two saddles.

Just last night my sister and nephew came up for a visit and she brought me two of the three Motobecane frames that he left me in his will. Unfortunately that was all she could fit in her car along with all of her luggage. There is still the one frame, quite a few sets of wheels, and a ton of vintage parts like cranks, freewheels, shifters, brakes, and handlebars that I still need to go pick up. You can imagine my delight when I saw that one of the frames is a Grand Record (not sure of the year model) with a Brooks saddle! The other one is possibly either an '82 or '83 Team Champion, though I'm not 100% sure since I haven't been able to examine them closely yet. Here's to hoping I'm right, though!

stevegreer

Final verdict is a '77 Grand Record and an '84 Team Champion.

Anyway, sorry to have hijacked your thread. But to answer the OP question, yes, if you have a chance to buy a vintage French made frame for $30... take it.

spock345

No problem, it is interesting to hear about these things. I fully intend to go and pick up the frame tomorrow and start working on it.

stevegreer

Update? Did you get it? Don't leave us hanging!