gitaneusa.com :: View topic - Ok, yes another question

scozim

In looking at my Gitane the specs say it's supposed to have a Maillard Helicomatic rear hub. The photos of these hubs that I had a sticker that said Helicomatic on it. My rear hub says Maillard with the number 42 on it and then a fainter 83. The front hub says Maillard with the number 49 on it.

greyhundguy

I'm not sure about Maillard, but I do know that Huret used a Date Code on many of their parts. Huret had a 4 number code...4875 for example. 48 was the week of the year and 75 was the year. In '75 the 48th week was the end of November. This may explain your #'s. Hopefully another list member knows if Maillard did the same.

Jay

verktyg

Before you go any further I think that you need to determine whether or not you have a Maillard Helicomatic rear hub. The numbers that you posted indicate that the hub was made in the 42nd week of 1983.

I posted links for 2 sites with information on Helicomatic rear hubs in several other messages. They are pretty easy to ID. Look for a ring holding the freewheel on to the hub. If it doesn't have a lock ring like the picture below then it's a standard freewheel hub not a Helicomatic hub.

Here's what they look like:

Here's the sites again in case you missed them:

http://www.sheldonbrown.com/velos.html#helicomatic

http://www.yellowjersey.org/helico.html

Sheldon Brown (RIP) didn't like Helicomatic hubs but Andrew Muzi at Yellow Jersey, Ltd. thinks that they are pretty good. My suggestion again is if it works and you can get a larger tooth Helicomatic freewheel or cogs then ride it into the ground. I think that Sheldon's main problem was changing broken spokes which would be the same with a standard freewheel and most cassette hubs.

Broken spokes usually result from poor quality spokes to begin with also spokes that are not properly tensioned.

Going to a wider rear hub to use 7 or more sprockets is more involved than just spreading the rear triangle. Any near do well self proclaimed bike mechanic can spread the rear dropouts but that usually results in the rear triangle being out of alignment with the rest of the frame. Also the dropouts will need to be realigned. This isn't brain surgery but it's beyond the experience of many of the hammer mechanics I've seen working in bike shops.

When the rear triangle is out of alignment the bike tends to track squirrelly because the rear wheel angles a little to the left or right of the front wheel.

When I got my 1984 Super Corsa frame (same as 84 Tour de France frame except blue not red) the rear dropouts were 127mm or 128mm wide, Someone was probably forcing a 130mm rear hub into the dropouts.

I took it to a local frame builder's shop and put in on his frame alignment table.I spread the rear triangle to fit a 130mm hub, realigned the rear dropouts plus the rest of the frame. The frame builder realigned the fork for me. It's now one of the best riding and handling bikes I've ever ridden.

You don't need a fancy setup to align the frame. Do a Google search plus Park Tool has some good instructions on their website.

Secondly, you may run into a problem of not enough room between the smallest sprocket and the inside of the seatstay , chainstay or dropout. This makes shifting difficult if not impossible because the chain gets hung up when shifting off of the smallest sprocket. The easiest fix requires some modifications to the frame with a file to make enough clearance.

The third problem you might run into is the amount of travel in the rear derailleur. I used a Simplex LJ rear derailleur and had to file down the stop that limits the travel to the largest freewheel cog.

Forth is finding a rear shift lever with a large enough "barrel" to wrap up the additional cable required to cover a 7 or 8 speed freewheel.

One other thing, you can get longer axles and spacers so that you can convert a 120mm or 126mm wide rear hub into a 130mm hub for a 7 or 8 speed freewheel. The problem is that the right side hub bearings are under the inner area of the freewheel and can result in frequent bent or broken axles because of lack of bearing support for the outer right side of the axle.

My 84 Super Corsa is now running a Shimano DuraAce 8 speed rear hub with a Simplex LJ rear derailleur. I found a set of Huret shift levers that let me index shift the 8 speed/Simplex combo perfectly.

Good luck,

Chas.

scozim

Chas,
Sorry, I missed the Helicomatic picture before and will look at that. I don't remember seeing that on the freewheel when I looked at it yesterday so hopefully it isn't one.

I've got a friend with a late 70's Sekai 2500 and he's been buying up Suntour freewheels in 6 and 7 spd configurations to get gearing he likes. Lucky for him they are readily available.

verktyg

If your rear hub isn't a Helicomatic then you have a few more choices. I think that you mentioned the the rear dropouts are 122mm wide. How wide is your rear hub across the locknuts? If it's less than 126mm it was designed for a 5 speed freewheel (there were some early 125mm wide 6 speed hubs).

You can sometimes put a spacer on the rear axle to change it to 126mm wide or put in a longer rear axle. You need a minimum of 3mm threaded axle hanging out on both sides of the locknuts. If you change the axle width you will need to have the rear wheel re-dished.

Everything that I mentioned about spreading your rear triangle still applies.

Suntour made some 6 speed "Ultra" model freewheels that had narrower spacing so that they would fit on most 5 speed hubs. They also made the same thing in 7 speed "Ultra" freewheels to fit on 126mm 6 speed hubs.

Shimano, Maillard, Sach/Aris also made some narrow freewheels. Again, all the warnings about derailleurs apply here too.

Chas.

verktyg

Judging from the picture of your freewheel, it looks like you have a standard hub not a Helicomatic. It could be a Maillard 700 Course a 700 Compact or an Atom 77B freewheel. What color are the spacers between the freewheel cogs? Are they colored plastic or metal?

Somewhere I got the notion that your hub is 122mm wide. If so then you probably have a "narrow" 6 speed freewheel.

Your 1984 TdF should have 126mm wide rear droupouts and a 126mm wide rear hub. A 126mm wide hub should be able to fit a 5 speed, 6 speed standard width, 6 speed narrow width and maybe a 7 speed narrow width freewheel. The 8 speed freewheels and many 7 speed freewheels were designed to fit on 128mm, 129mm (bastard sizes) or 130mm wide rear hubs.

I have several 7 speed Suntour "Ultra" narrow width freewheels on 126mm rear hubs. On at least one of the bikes I had to file some clearance on the bottom inside of the right seat stay so the the chain didn't get caught when I shifted from the smallest sprocket to a larger sprocket.

Chas.