bmartinek

Hey guys, first time posting here. My GF and I bought a vintage ~'86 Gitane tandem here in Germany and want to get it on the road to ride around. It'd pretty clean for its age and looks like it just needs a couple parts. I've searched around on a couple threads but didn't see some of the things I was looking for.

1. I bought a pair of 28x1.75 gumwall tires, will these fit? We wanted a bit more cushioning for bumps

2. It looks like the original front handle bars have been poorly retrofitted, so I'd like to fix that. most likely drop bars are they standard 25.4mm size?

3. Alright I expect to take some heat for this, but I like modern aesthetics and power of integrated shifters and brakes. Assuming I drop the Drag brake (Nuremberg is pretty flat) Would there be other issues.

4. My rear derailer is exploded, so would like something more modern there as well, Looks like 130mm for the hub size I think. Any experience this I measured via calipers seemed about that.

5. If I am upgrading the other stuff, wheels would be nice as well, since the old ones do not look so grippy for the brakes.

6. I've looked around about the aluminum deoxidizing, and saw the Mother's mag polish is popular, but I don't want a mirror finish more of a satin, without all the cruft and sanding polishing marks, suggestions?

Sorry this is a lot and thanks for reading! Any advice is greatly appreciated Will post pictures when I get those rights...

obrentharris 

I don't know the specific bike so I will not address the issues of tire and handlebar fit but items 3,4,and 5 on your list are interrelated and I can address them:

If your current dropout spacing is indeed 130mm then you are good to go with frame spacing. If, however, it is 120mm or 126mm then you will have to respace to accommodate the newer cassette wheels that are required by the modern integrated shifters. Yes you will have to replace your rear wheel from one that fits a freewheel to one that fits a cassette. You must buy your rear derailleur, rear hub and shifters in concert. Indexed shifting, which is built into the integrated shifters, requires matched components. Shimano shifters don't work with Campagnolo gears and derailleurs and vice versa. There are even compatibility issues between the various generations of components within one manufacturer. You might want to spend some time looking at this thread which is all about bikes that have undergone the same conversion you are contemplating - https://www.bikeforums.net/classic-v...i-s-ergos.html

You will also probably want to find modern front handlebars as they are designed to accommodate the hidden cable routing of the integrated shifters. Their shape also provide a more comfortable hand position on the hoods since the brake levers with integrated shifters are shaped differently than traditional single-purpose brake levers.

I don't have an easy answer for your polishing question. I have accomplished the satin finish that you are after by sanding with 600 or 800 grit emery paper.
Brent

bmartinek

Thanks Brent,

From my research it looks like a 1986 Gitane Tandem. I would post a link but can't yet.. Ughh

Yep I agree everything would have to be done at the same time. I'm lucky to have two very modern bikes and its hard to go back so far. I was never a fan of frame shifters even as a kid.

I guess the big issue will be removing the drag brake.

bmartinek

One thing that could be tough is the crankset. Ideally it be nice to keep it all as one set, but that will not be possible as those old Sugino RT triple cranks are venerable old.

obrentharris 

One solution to the crankset issue is to use Campagnolo 10-speed shifters with Shimano 8-speed cassette and derailleur. This combination shifts very nicely. The 8-speed chain is wide enough that it plays nicely with the older chainring spacing on your original cranks. The Campagnolo front shifter is ratcheting rather than indexed so it also plays nicely with the older chainring spacing. I would guess that a complete Campagnolo 8-speed system would have the same advantages.

Hopefully others will chime in here with other combinations that work.
Brent

jeirvine 

Pic assist: https://ibb.co/album/gJAHqa

bmartinek

Thanks Brent, definitely some good info on that thread. Also conversion from a quill stem would be nice for vastly nicer ergos. I love the Specialized Hover Bars super comfy, but it would not look so period :-)

Which Campy shifters would you suggest, Any 10-speed will do? Perhaps Centaur or Veloce?

Any Wheelset suggestions? I have read 36H and up and they are 700C already fortunately.

Since you are in the Bay Area, if you need powder coating for your bikes, Leon's in Oakland does a great job and they are affordable.

palincss

Perhaps you've forgotten, this is a tandem. Tandem back wheels are much more stress than singles, and modern tandem back wheels use anywhere from 145-160mm dropout spacing. Even back in 1976, Jack Taylor tandems had 135mm spacing for a 5-speed freewheel hub. The additional width is in aid of reducing or eliminating dish, which substantially weakens a back wheel. On singles, there's a lot less weight so you can get away with a lot weaker back wheel than you can on a tandem.

Incidentally, the back wheel shown here on jeirvine's Gitane isn't even a standard freewheel hub, it's a drum brake. Going by whatt I remember of my old Gitane tandem, it looks like an Atom.

SJX426 

Often they will have a higher spoke count as well. My Burley Duet has 48 spoke wheels.
[IMG]Carols Tandem, on Flickr[/IMG]
There are a number of attributes about tandems that make them unique from singles.

bmartinek

Wow SJX, thats a nice looking tandem!

@palincss Actually that is my bike, Jerry posted the pictures because I don't have those rights yet, or more than 5 posts per day

You are correct, that is a Atom drum brake on the rear. I took it off last light, jesus it weights 3.7kg! Over half of what my Pinarello weighs!

The rims are cool old Mavics. Will post a picture in a bit.

bmartinek

Last night I put new tires an tubes on. The 1.75s actually fit, but its a bit tight in the fenders. The bike may have had the original tires on it.

Also I put modern cantilever brakes on as well, and started to adjust the brakes. Ughhh It becomes an interesting timing problem to get front and back to actuate at the some time since it is single pull.

bmartinek

Tomorrow I will head to a friends shop to see if he has a 5 speed deraileur. Maybe some better bars. The ones on there now we not done well and the cables are a bad pull angles.

Sorry these are short messages, without images, but I need to get past 10 posts to post images...

bmartinek

Should be post 10, I wonder if I can add images or links yet?

...

Nope...

palincss

They'll eventually synchronize with wear, but it doesn't hurt if the fronts come on first. It's impossible to do an endo on a tandem.

JaccoW

Why do you want to remove the drag brake? Modern disc brakes might be fine without but cantilevers on a tandem might actually need them.

And new ones are getting rare and expensive.

spircix

Please, keep posting and, when you can, post as many pics as possible. Really nice-looking bike, I would love to see the end result
Personally, I would leave the patina, because it goes great together with the frame. I have a soft spot for patina and visible marks of wear on everything

JohnDThompson 

If it's like my '84 Gitane tandem, it's a 40-hole Atom drum brake hub with an oversize 11mm axle (and widened dropout slots on the frame to match), metric freewheel thread, and an Atom 4-pawl "Tandem" freewheel.

bmartinek

ERRRMAHGERD!!!! Should be able to post photos now!

So last night I got some some steel wool and removed some dirt oxidation. I would like it to be clean, but not a museum piece by any means. Also useable for my GF and I as a grocery getter.

Spircix here is a patina/oxidation picture for you of the front fender. Love the yellow light bulb

bmartinek

Hey Jacco,

Well, changing the wheels would be for several reasons:

1. Weight, the rear weights 3.5KG, I live in a flatter section of DE.
2. Better braking surface (box section) and dual wall wheels for heat capacitance
3. Modern Gearing options for cassette and shifters.

I think I will get it on the road first, feel it out, and then see what is needed. I would keep all the spares.

bmartinek

Here are a couple other pictures of the seat conditioning and other rando pics:

Before:

After:


Awesome vintage Mavic logo:


Sad old tires and brakes:

jimmuller 

Nice looking bike. About that rear wheel, DO NOT THROW AWAY THAT HUB! You said the rear brake exploded (at least it didn't asplode). Did you mean the drum brake or the calipers? Either way, those parts are valuable to some of us. For example I had to cobble a spring from a Shimano spring for our Peugeot tandem.

Your rear drum brake appears to be the original Atom, a functional brake indeed. I can't follow the cable routing in your pics but one original way they were rigged was both F and R calipers were operated by one hand, the drum by another. The drum was intended to be a drag brake to control speed on long descents without building up heat in the rim. But it provides enough braking power that it can be used as a conventional brake. Anyway, if you are switching to a different wheel or having that rim strung on a different hub, I may be interested in the hub. Some of the parts are scarce, like the axle, which I'm guessing has M11 threads.

Enjoy the ride. Welcome to C&V!

jimmuller 

Groceries? We use ours for that sometimes. My sweetie insists on taking pics of me. Yes, those panniers are carrying 30 to 40 pounds of groceries.



Picking out more weight to carry home.

bmartinek

\

Hey Jim, It was actually the rear derailluer that exploded. Also very cool grocery getter!



Also yesterday while polishing the rear fender I bumped the front derailleur with my hand then it fell off. I mean really!?!?! why would you make a clamp out of plastic!

spircix

The bike will look superb in the end: blue frame, satin chrome fender and other hardware and, if you'll get gumwall tyres, that will look perfect! Gosh, I kinda want a tandem now

jimmuller 

Ah, as I said earlier, welcome to C&V (you young whippersnapper). It is part of the heritage. Really.

Check out: Simplex Prestige derailleur (532)

and for the company overview: Simplex derailleurs

At one time Simplex was the largest derailleur manufacturer in the world. Then Lucien Juy, founder and chief engineer, made a momentous decision to use a new material for all (or almost all) of their derailleurs. This material was a new plastic from DuPont named Delrin. It was light and strong and worked well, produced lighter derailleurs than most competitors. It had only two problems, without any sort of steel or aluminum reinforcement it could wear out fast, and it didn't age well, especially when exposed to harsh outdoor environments. Peugeot and Raleigh and others made zillions of bikes with the Simple Prestige, and for a few years they worked as well as any others. There are still plenty of good Prestige derailleurs around. But eventually they might break, especially the bracket holding the FD to the ST. About that same time Suntour and then Shimano began selling decent derailleurs too, especially Suntour's patented slant-parallelogram models which worked noticeably better than everything else. That started Simplex' decline. The original company closed in 1995 though someone is making new derailleurs with the name Simplex. With sufficient reinforcement their models were quite good, but they had lost their hold in the marketplace.

They made a series of GT derailleurs that work well on a tandem. SX410/610/810/GT, maybe with a different suffix than SX. I can never remember which is which. Velobase.com has listings. If you want to maintain some amount of cultural accuracy on your bike try to find the SX410GT, or either of the other two.