Hi there,

Lately my 1983 Schwinn Le Tour has been experiencing frequent chain pops in 5th and 6th gear. Last year I replaced the free wheel, the crank, and recently the chain. My local bike shop just told me that I will need to replace the rear derailleur as some internal spring can no long provide the pressure necessary. It currently has the factory installed Shimano Altus derailuer. They told me that they have inexpensive $10 derailluers in stock they could replace it with, but they felt they were of dubious quality thought I should seek out something better on my own. I really would don't want to spend an arm and a leg, and I have no idea where to even look. Are quality new replacement available? Where would I find a replacement 83 Altus?

I suggest getting a modern derailleur of Deore quality off eBay. It'll last longer and shift more reliably than what they had in 1983.

There is no good reason to be period correct and stock NOS parts are almost impossible to find. Good luck.

I am in no way concerned about being period correct. Just want something that works. What I don't understand is how to figure out what model I need.

You don't need any specific model, the majority of derailleurs ever made will work for that bike. The only concerns when replacing friction shift deralleurs are whether the derailleur supports whatever size your largest rear cog is (probably a 28 tooth) and that it's total capacity is at least (teeth on big rear cog - teeth on smallest rear cog) + (teeth on big front chainring - teeth on small front chainring). For example, if your freewheel is a 14-28T cluster (pretty typical for bikes of that vintage), your big front chainring is 52 teeth, and your small front chainring is 39 teeth, you need a derailleur that has a max capacity of at least (28-14)+(52-39) = 27.

To simplify this, any derailleur designed for a mountain bike will work, as they'll be designed for large rear cogs and large total capacities. Mountain bike derailleurs include Shimano's Altus, Acera, Alivio, STX, Deore LX/DX/XT, and Suntour's XC series, among several others.

Yup. Deore is Shimano's mid range derailleur. Its solid and reliable. And its inexpensive and readily available.

I replaced my '77 Super Le Tour 12.2 RD (and Front) with Suntour ARx.
It works great, and is somewhat period correct.

I have a few spares if you need one.

I would want the derailleur to at least look like it belonged on the bike.

The AR or ARx would be fantastic, as would pretty much any Suntour RD. There's also the XT stuff- it's fantastic and bombproof- and I think the MT-60 Deore stuff doesn't get the props it should.

I just put a modern Shimano Acera on my 37 year old touring bike. I think it's a pretty good derailleur for the money (30 USD here in Sweden). It doesn't look too bad on a bike like this and would work with most Shimano indexing.

If I were putting it on an actual mountain bike, I'd have gone more upmarket, but for commuting, fun rides and light touring, I'm sure it'll be fine.

I just bought a Shimano Altus brand new. It looks like a nice piece for $25. I didn't want to spend too much on my son's old Raleigh.

Marc