Put out to rust.
 

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Bought this one from someone who was not bicycle guy. It was stored outside in his gsrden,probably been there for a long time. Sad with so much rust, bearings sre smooth. Datecode on RD is 1975.
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That is a great bike. I like those honeycomb drop outs.

Evaporust will take care of the parts. I'd give the frame an oxalic acid bath. The rust on the chrome might be tough.

No matter how it looks, it will probably have an awesome ride. Gitanes of that level are special, particularly those with full 531 frames!

I spent a year on an ItalVega that was a lot worse off and it came out nice. Mine had been left in a field in Moro Bay California, a real foggy cool beach town. I used many different methods from scraping the rust off to very fine steel wool. None of the rust had entered the bearing races or inside the frame. It is my patina bike and I like the way it looks. You can read about it on my blog. joesvintageroadbikes.wordpress, Rusty Resurection.

He would HAVE to be a non bike guy to do that to a high end Gitane!

Great potential on that bike. Please make it all it can be. But that saddle, is that a Cinelli Buffalo #3 ? I road 80 miles on one of those in 1976. I was crippled for a week! Just looking at it gives me nightmares

Evaporust, wax and ride it as a rat rod/patina/survivor. Nice rescue

Is that a Tour de France? Funny, that's how I got my '84 tomato red Gitane TdF. It was in a friend's neighbor's front yard. It was in Texas and not in the direct sun so despite a the crankset being frozen to the spindle and the delrin Ofmega components turning to dust, it was in pretty great shape. I think the guy was happy to get rid of some "trash"!

That doesn't look too bad, to be honest. Check the inside of the tubes, and if the worst of it is the fork/stay ends, then you could dip them in Evaporust without having to use too much (tall, narrow container).

Unfortunately, our bikes are rusting in our humid barns. We have no choice, as we have no garage, and our house is small. I disassemble and grease and reassemble as frequently as I can, but I'm losing overall.

Definitely not a bike guy. That had to have been someone's pride and joy once upon a time.

Cosmetically, evaporust or oxalic acid followed by chrome polish will likely make that look acceptable. The chainstays are pretty bad though. I'd consider a rechrome and repaint down the road, if you really like the bike, and plan to keep and ride it yourself. As you probably already know, when rust is removed like this, it doesn't actually repair the damage. What you really are doing is polishing the underlying steel so that you don't easily notice the chrome is gone in spots, and it can easily rust again if not kept after.

looks like a super olympic, top of the line. ride the hell out of it

Holdsworth
 

There’s a jackass a couple block over from me with a once nice old Holdsworth (all campy) sitting propped up outside on his fence. He had it in the back of his pick up with a bunch of scrap. I stopped and offered him 200 dollars for it five or six years ago, and he says: “oh **** I forgot to take that out back, my brother tells me it’s worth 1500 dollars”. It’s been leaning against the fence outside ever since.

Very nice find. This deserves to be rescued from the rust monster.

Some wadded up aluminum foil and light oil will fix that rust on the stays and fork socks. My World Voyageur looked just like that. Cannot tell it was ever rusty now.

Here is a before and halfway through the process.

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The chainstays are bad, the rest of the bike has "patina" and I got a lot of the rust off with alluminium foil and some bio hubcleaner. Headset and BB are in great condition, haven't opened the hubs yet. Quite a lot of rust on the spokes, how do I know if they are safe to ride? This will be my only proper vintage bike, must get some old shoes for the pedals(and some Binda straps).

The spokes would be safe to ride on if they are tensioned to an adequate and sufficiently-uniform tension level for the loading that they will see.

They typically would only fail one at a time if ridden long enough to bring on fatigue failure. I've ridden much worse-looking spokes but the brand of spokes can be much more important than differences in the level of corrosion..

The chrome does look a bit rough but the paint and decals sure look pretty to me. A truly awesome find! I’d keep it forever and ever if it were mine.

That is very good to know. The hubs were gunked up with old grease but the races and cones look smooth and I think the double butted spokes and Nisi rims will be a nice wheelset for the bike. A bit intimidated by 43-21 as my granny gear so this will not be a bike for the mountains. Strange thing with the rims, someone has drilled two shallow dents between every spokehole, drillium perhaps? It is fun working on this bike, old campy parts are really well made!