Bruce27

I'm getting to an age where I really appreciate a granny gear at times and a more relaxed ride so I bought this NOS 1984 Trek 620 last week. After sweating out the shipping, it arrived the other day in great shape, and amazingly, it truly is a 30 year old bike that has had no real use. Paint is gorgeous, already ordered tires, rim tape, tubes, brake pads, bar tape etc.. and I'll probably put new grease in the bearings. I'm also thinking of swapping out the rear derailleur and putting on an old Suntour VX-GT long cage I have (good or bad move?). My intent is to have this bike as my main rider.
Really don't want to throw too much more additional dollars into it right now, but to those members who own or have owned this model, what else would you do?
Thanks all in advance.

JohnDThompson 

In my experience, the stock Duopar performs better than a SunTour VX-GT, but not by much. Why do you want to swap it out?

wrk101

I swapped the Duopar with a nice Cyclone GT generation derailleur, just for the heck of it (I love vintage Suntour, and the first generation Cyclone GT was a beautiful derailleur). I also installed bar cons and 700c wheels. Of course, someone came along and just had to have it, so off it went. I do have its matching brother in my project queue.

The changes I did would not be cheap unless you have an ample parts bin. First generation Cyclone GT derailleur set can go for about $100. Bar cons are also not cheap ($40 to $50 market value).

Bruce27

I read some horror stories when I was doing a search...and it looks very "industrial". If you think it's better, I may just leave it then. Appreciate the input.

Bruce27

Yes.. I understand and would have preferred 700c's but don't want to go crazy dollar wise as I already spend a decent amount for the bike. Just want to get it set up in a reliable manner and do some riding.

due ruote 

Other than the things you mentioned, esp. grease, I doubt there's much about that bike that needs to be changed. Get the fit dialed in, put a couple thousand miles on it, then decide if you'd be happier with barcons, etc.

Personally I'd ditch the reflectors and spoke protector but I suppose one could argue they serve a purpose.

The Golden Boy 

Congratulations on the 620!!! They're super awesome fantastic bikes!

I have had a DuoPar horror story.

However, I would take any suggestion by John Thompson with approximately 400x the weight as anything I would say. ESPECIALLY when it comes to Treks, ESPECIALLY ESPECIALLY Treks that were made during his tenure there.

For whatever it's worth, I have a Suntour XC Comp on my 620. I love those late Suntour derailleurs.



I'd say leave the reflectors, and only ditch the spoke protector if it gets dirty and yucky looking.


As far as anything else- I like the Avocet Touring saddles. I personally don't like the DuoPar- but I'll be trying out the DuoPar Titanium unit on my 720- at least for a while. I left the stock Sachs/Huret FD on, but I've got a Mountech FD that I'm thinking about replacing it with, for no other reason other than it's Suntour. My 620 did not come with the Maillard hubs, but I would look at replacing those- as the Helicomatics have a... reputation. I don't know how you feel about the pedals, but I've replaced mine (I think they were SR150s) with some no-name ATB pedals with clips and straps.

Let me know if I can be of help with anything!!!


Again, congratulations-

JohnDThompson 

I can only speak from my experience. I still use the original Duopar Eco I purchased new in 1978 on my commuter bike, and it's never given me problems:



Nor do I recall any rash of complaints or problems with them while I was at Trek (I was actually the Warranty Return Inspector, among other things, at the time your 620 was built, so I would have easily heard about any such problems. Huret "Jubilee" front derailleurs are another matter!). Not to say there aren't any problems, but I suspect people are more likely to post about problems than "working as expected" which may account for the horror stories you've read.

The Golden Boy 

John, what do you have on your glorious 720 (or is it a 728)?

Bruce27

Pleased to meet you and thank you for the response. This kind of input was exactly what I was hoping for. I'll give the Huret a go before I make any changes. I only wanted to change what was necessary so this goes with my initial preference.
Must have been exciting working there during that time. Purchased my 715 new in 81. Not to be nosy, but were you also there in 81?

JohnDThompson 

Yes, I was at Trek from 1980 to 1986.

JohnDThompson 

It's a Duopar Eco as well, but a newer iteration. I still have a couple NOS titanium Duopars, but haven't felt a compelling need to use them yet.

Bruce27

Thank you very much, especially the "be of help" offer . I also read about the Helicomatic but not planning on doing heavy touring so I'm hoping just a clean up and I'll be good...until the next cleaning. Just wanted a versatile bike to do road, dirt road, and climb hills without struggling too much. I have a comfortable gel seat and Shimano SPD M737 pedals that I use between bikes that will end up on this bike. Regarding the Duopar, it may have been your horror story that I read and was referring to. I did notice that the DR cage tip hangs kinda close to the spokes when the chain is on the large end of the freewheel. The dropout looks straight to be but I'll clean it up, reinstall, and see how it goes from there. I will certainly be watching it from the start. I take it I just pop the plastic piece out and there's an allen bolt under it for removal?

Bruce27

Very cool. I have a fond attachment to my 81.

Wheels Of Steel

Raise the seatpost so water can't enter the seat tube via the flutes.

The Golden Boy 

Mine had a different cover housing- if you do ever remove the DuoPar- twisty tie or zip tie all the bolt/washer/tab pieces. The little keyed washer is completely unobtainable.






What happened with my DuoPar is that it mis-shifted. The chain got pulled between the upper pulley and the inner cage plate. Something either bent or got damaged and the chain started continuously jumping into there- every little bump it would happen. I would have to dismount and yank the chain out- getting my fingers and glove (and my white bar tape) all filthy, and it happened all the time. After this happened, I started finding other things on the internet about the derailleur being "fragile."





I think it's a neat looking piece- not as sleek as like the XC Pro/Comp or Shimano Deore stuff, but "industrial" is a good word to describe it. It's not as outrightly burly as something like the AG Tech or LeTech (I've heard of those being referred to as "rock crushers"), but definitely industrial.

I just got a Titanium DuoPar on my 720- so I'm going to wait with swapping it out, more or less based on John's testimonial.

JohnDThompson 

Yes, you can use e.g. a spoke to push it out from behind. That's safer than prying it out from the front, which often breaks the plastic. Although that's just a cosmetic problem. Another thing you might run into (although I think I've only seen this on Jubilees and the titanium Duopars) is that some versions of the mounting bolt are locked from behind with another Allen-headed bolt:



You'll want to loosen that first before trying to remove the derailleur.

Bruce27

Thanks for the tips. I know I would have tried prying that plastic cover from the front. Would never had thought about popping that out from the back, nor would I have known about a lock from behind. Here's a pic of mine. Seller must of had this on the small back sprocket and the small front chain ring when taking this picture. I'm sure I'll have more questions as things move along. Appreciate all the responses.

The Golden Boy 

You'll see how loosely that arm swings around.

So now you need a "family" picture- your 715 with the 620!

The Golden Boy 

Hey Bruce, how's the bike coming along?

More Pix!!!




By the way, I wanted to say how classy your dropouts look- nicely beveled and brazed.

Bruce27

Did a major clean up. Here's the transition on the brake hoods. I'd like to say this was the easy part so far, but almost had to break out the chisel.

The Golden Boy 

If you don't want to have the reflector bracket be the front brake cable stop, you can order a quick release cable stop that mounts to the headset for like $5. The ones I got were Shimano branded, but I've seen others that are DiaCompe branded.

Bruce27

Thanks. That looks like a good clean option. I'll certainly check it out.

wrk101

OK, for long term, the one thing I would change for sure is the helicomatic rear hub/cassette combo. Obsolete for almost 30 years, cassettes sell at a premium, takes a special tool, etc.

Bruce27

If I wanted to keep the same rim, any recommendations on a replacement rear hub?