marius.suiram 

I have this project to finish.
The bike came with Sachs-Huret derailleurs and shifters.
I thought that the rear derailleur should be the titanium Duopar model, but it is the Eco model. Which one is correct?
In the catalog it is no specification of the model.
The crank set is Shimano 600. The pedals are Shimano 600 too, but they are not moving. Can the pedals be serviced and regreased? I never did this. Anyway I have another pait of replacements.
Question: should I replace the derailleurs and shifters with Shimano 600?
Also i don't think the brake levers had original those safety levers.
I don't like the bars/stem with that cable stop in the reflector support, but I can replace the stem with a SR witch has a hole in it for the cable stop.
Any reply is welcome. Thanks.
Some pictures

marius.suiram 

No wheels.
I have a set of wheels with Maillard Helicomat rear hub, but I think they were original one year after.

LBCwanabe 

That’s nice!

The Golden Boy 

The Trek 620 had the Eco, the 720 had the Titanium Duopar.

No, you should not use 600 derailleurs- the Sachs/Huret front is a great FD- I'm not a fan of the Duopar- but if it's in good shape- I'd use it. I would probably swap out those shifters- get some cool ratcheting shifters or bar ends.

I wouldn't use a stem with the with the hole drilled through it- I'd consider just getting a different headset mounted cable stop and ditch the reflector and bracket.

marius.suiram 

Ok. I had a 720 two years ago, which i remember it should have the Duopar titanium, I thought the 620 has the same.
I have some bar-end shifters, but Suntour.
I will leave the derailleurs if they are working good.
I am not sure what cable stop to use, but I will go tommorrow to the local Bike Coop and see what they have.
What about the wheels? People are saying that the Helicomat hub is not good.
Thanks for your advices.

Hobbiano 

You might want to disassemble the helicomatic hubs and if the cones and races are in good condition go ahead and overhaul them and use them. The cones seem to go first and replacements are difficult to find. They came in at least three levels on quality. On the Treks that used them the 500 series had the cheapest ones (Helicomatic Sport), the 600's had a better quality (Helicomatic Luxe) and the 720 had the best (Helicomatic 700). The freewheels are specific to the Helicomatic hubs. No other freewheels will fit. The front hubs are longer lasting than the rear.

Here is a link to a video on how to overhaul a Hurret Duopar derialleur:

Chr0m0ly 

Isn't that an '84? The '83 620 had caliper brakes. This one is much more desirable in my opinion👍

ironwood

It isn't an '83, all the 600 series that year had caliper brakes, not brazed on posts for cantilevers. The '83s are good candidates for conversion to 650B.

ryansu

Nice score OP I am in the midst of an 87 Trek 520 overhaul have fun with it.


Rust bath

Iowa10Speed

I have a 620 like yours. You'll have a great bike when you're done. Your paint is nice. It's amazing in the sun.

My experience is similar to the other posts:

• Yours is an '84. The cantilever brakes and all your components match the Trek catalog specs. The chain stays on the '84's are longer than the '83's which is usually a better geometry for touring bikes (45. cm length vs. 44)
• The derailleurs are smooth and mostly trouble free. (I have a 620 and 720. Both shift well. However, I had another 620 that jammed the rear derailleur when the bike was rolled backwards too quickly. It was still rideable as long as you were careful when moving the bike Others have the same problem. Search the forums for more info if you have that trouble.)
• Helicomatic hubs are smooth but some had pitted cones. My front wheel was pitted, but I kept them because I couldn't find replacements.
• I eventually got another wheelset for my 720 so I could use standard thread-on freewheels. Shifting on the stock freewheel was poor compared to Suntour and Shimano freewheels. I got tired of fussing with each shift. Also the original freewheels were worn. Replacements are hard to find and expensive.
• Overhauling the pedals is easy.
• The headset uses roller bearing instead of ball bearings. I wasn't good at adjusting them, but once I got it right they work very well, and are sturdy.
• Ratcheting Suntour shifters are great. The downtube Sprints are smoother and more precise than Suntour's other models. (The Sprint 9000's are also an option. They can be set to indexed or friction).

• Vintage Trek is an incredible site about steel Treks. Serial number charts give the exact day the bike was built. Also catalogs, history and much more.

marius.suiram 

Yep, my mistake. I checked the s.n. on the Vintage Treks site and it is a 84.

marius.suiram