Advice/options on upgrading 1984 Trek 620 drive train (N600 28-45-50 crank)
 

I recently picked up a 1984 Trek 620 touring bike that saw very little miles. We just completed a 100-mile weekender tour and I've decided I need to upgrade the drivetrain. It is being ridden by my wife who is not the most adaptable to mechanical quirks.

Primary problem experienced by my wife is the shifting (which is mechanically fine and has a brand new chain). The crank is a Shimano N600 touring with 28/45/50 rings. 5-speed rear with downtube friction.

a) The 28t -> 45t -> 28t jump is huge. I think it is clunky, difficult, and prone to dropping the chain. Seems like a really weird combo.

b) would prefer at least indexed shifting for the rear.

At this point I'm considering these options:

Option 1: Ditch everything (but keep 27" rims**), Bar-end shifters
-- front crank replacement: Sugino XD-350 (28-36-48)
-- rebuild rear (27") wheel with new Shimano LX freehub. Assume spreading 126mm frame to 130mm hub is ok?
-- DA bar-con shifters w/ 9-speed cassette
-- Deore rear derailleur.

Option 2: Bare essentials, indexed down-tube shifters
-- if possible, replace the 45t cog with something like a 40t cog?? Advice on what to get?
-- find indexed rear shifter, possibly upgrading from the current 5-speed to a 7-speed freewheel cassette?? Rear spacing is 126mm. Possible? Do I need to redish wheel?
-- Keep everything else-- derailleurs, hubs.

Any advice appreciated.

** not really considering 700cc conversion. I tried mounting 700cc wheels, and while the cantis reach with adjustment, I think they are mechanically disadvantaged. Only reason I would want to upgrade is to get fenders in there given the ridiculous 1/4" of spacing available between the front tire and fork crown.

Half step with a granny is pretty common on vintage touring bikes.

To me, touring bikes should have barcons, so I like that plan.

If you want something really crazy, you have to see the Stronglight double I pulled off a 1970s Peugeot. 51 tooth big ring, 49 tooth small ring.

wrk101-I really like that specialized sequoia on your flickr...its my size too

I agree with Work that 1/2step +granny sounds pretty normal for the period. I do not have alot of experience with them but I believe you normall use the 45/50 and the 28 is a 'bailout' for the tough stuff. So she should be shifting between the 45 and 50 more.

I have some questions.

What is the FW?

Is your wife comfortable with the DT shifters?

How much does your wife weigh and how much gear are you lugging?

You might be able to swap out the rear axle and out a 7spd FW, that will give you a wider range, and some 7spd DT shifters and an MTB style RD like a older Exage or RSX. That would same the hassle/expense of a wheel rebuild. You could pick up Sunrace DT shifters, FW and RD for about $50 (the FW is only 12-28 though)

An LX hub will most likely be a 135mm rear, unless you respace it...which is a bit of a job.

There are a lot of variable at play here.

If the friction shifting is fine, and the gearing is OK, then worry about the only problem you say she has: the gap between the 28t and the 45t rings, which can be handled by practice, practice, practice OR finding a more 'tweener ring.

If you want to go to indexed, you're still going to be dropping the chain on that setup, because the L side is still going to be friction. The rear shifting will be easier. If you decide to do the index upgrade, I recommend getting a modern crankset, triple or compact, to go with the other parts.

DT indexed may not work on those braze-on bosses without a little modification, so look at that first before you go out and buy everything you need and then not be able to use it.

If I was going to keep the frameset and upgrade, I'd simply swap in some modern wheels, or at least a rear hub. If rear spacing is 126, you can go to the "standard" 130 with just a bit more effort, or elect to cold set. I've never had to re-dish, and you shouldn't have to, either. Then I'd probably go with Ultegra 8sp or 9sp bar ends with an SRAM cassette, an indexed RD, and either a 52/42/34 modern triple crankset (a square taper would likely fit your BB) or find a square taper 50/34 compact. Your present FD should handle either one, though you'll have to raise it for the triple, which may mean a longer cable and maybe some changes on the routing near the BB, depending on the configuration down there.

For my wife's 1983 Trek 620, I did something similar to what you're proposing. But because the bike came with DiaCompe sidepulls rather than cantilevers, I could go to longer reach dual pivot brakes and 700c rims.

The gearing is now 26-36-48 on the front, making use of the Sugino AT crankset that came stock. On the rear, I went 9-speed 11-32 SRAM cassette, if I remember right. This gives her a wide range and allows quite a bit of gearing options on each chainring. For shifters, I used Dura Ace 9-speed barcons, running in indexed mode on the rear. Works like a charm and she's pretty comfortable with them now. But my wife rode DT shifter bikes back in the late 70s and early 80s.

The 620 is a fine bike, by the way. I hope that you and your wife really enjoy it over time.

Phil G.

If inded you do have those funny shimano round bosses, there is a pretty good thread somewhere on reshaping shimano housing stops to fit. Try searching Raleigh Wyoming that might bring up one thread with reference to others.

I have a Trek 520 with Deore RD & FD setup. I can't recall if the freewheel is still the Helicomatic. It has trigger shifters on a bullnose bar setup. If it would help, I can take a few detail photos for you, before the end of the week.

Some Shimano 5-speed

Hard to say. I think she was trying to make them work but I could see (from riding behind her) that it was kind of uncomfortable for her. Not sure if more practice would just solve everything or maybe I just do bar-ends which I think are easier.

125 pounds and we were lugging only about 15 pounds each.
Yup, seems like Sunrace DT shifters would be the easy part to procure. Do they still sell new FWs?

On the other hand, sound like people are recommending that I upgrade the crankset if I replace anything in the rear. So I may just do that and then might as well rebuild the rear wheel with a 130mm hub (Shimano 105 or something...commentor was right that LX is indeed the wrong spacing)

IMHO... keep the 600 crank set, swap chain rings to the sizes you want, and use friction style bar ends.

The 74/ 110 BCD pattern has the widest chain ring selection out there, so you should be able to find
ones that will give you the gears your wife needs. 28/40/50, or 34/42/52, perhaps? Stick with a 7 speed
freewheel to keep the cost down. As Bill said, bar cons are the way to go with that steed, and I bet you
can find some 7 speed indexed Shimano BS-50's and an older MTB R. DR that will do the job, like an older
STX or STX-RC. Or, just stay with friction, and use a set of SunTours.

:thumb:

EDIT: BG & Bill are correct... most triple road bikes from the period were ½ step + granny; either 28/45/50 or
28/44/50 if the bike was spec'd with BioPace chain rings.

I like this idea. I can try a set of new Shimano BS-64s. These are 8-speed shifters but the spacing is similar to 7-speed which means I can try a 7-speed Freewheel and if that doesn't work out, just get a new hub and 8-speed cassette.

I've never swapped chain rings in a crank before, but I assume there isn't huge compatibility differences? I.e., a Sugino 40t ring with 110mm BCD would work alright?

+1 Even indexed barcons are just indexed rear, friction front. Personally, I MUCH prefer friction front as it allows for ultimate trimming. And I like indexed rear just for convenience (but friction is fine too).

The 620 is a wonderful bike in almost all respects. I do think Trek screwed up by not putting bar end shifters on this bike, but that is a relatively easy, and not too costly, fix, if you go all friction. The Suntour friction barcons are the standard for that era.

Due to motor limitations on my part, I often "borrow" the two big rings from a MTB donor crank, and replace the two road rings. I usually end up with something like 48/35 or so +/-, making it the thrifty guy's compact double. I've done that on several road bikes with doubles. I need to do the same on a triple.

They also screwed up the fender clearance with 27" wheels! There is 1/4" clearance between the tire and the top of the front fork crown! 37mm width there. I think I can probably squeeze a 35mm fender in there.

But yeah, my wife tried out several touring bikes. She did extended test rides of the Surly Long Haul Trucker, REI Novara Randonee, etc. Everything felt "ok" but not great. She took one ride on this Trek 620 on Craigslist and was sold.

The Sugino 40t x 110BCD chain ring would work just fine. I bet the bar cons would work with a 7 speed freewheel, too.

I have Shimano 9 speed bar cons set to friction on my rebuilt '83 Trek 620 which has an 8 speed drive train, and I think I'm going to swap them out for a pair of SunTours.
Bill's right; they are more period specific, and the standard for C & V touring rigs.

With only 150 or so pounds on the bike you should be fine repacing/dishing the wheel for a 7sp FW. I saw today Sunrace even seems to make an 9. I have a few low milage 8s laying around but I think the biggest cog is likely a 25.

I think other online retailers have them too but I was looking at Niagara this morning to try and get my facts straight before posting, and they had everyting. I believe the Sunrace stuff is shimano compatible so you could use a nicer shimano RD.

But first you need to check those shifter bosses.

http://www.niagaracycle.com/index.ph...4847b6ef7cb5a0

Well, I just picked up two 1984 Trek 620s, both my size! So I will be trying out some changes.

I have an '83 Trek 520 where I had similar questions. I ended up changing out the 45 ring for a 36...and replaced the cup/cone bottom bracket with a cartridge. If this were my only issue and everything else on the bike were good, I'd probably just go this bare bones route. I would consider the barcon friction shifters everyone mentions. I don't like downtube shifters and find the bar end position nice on a touring bike.

On my bike, the wheels weren't in the best shape. So, I replaced the wheels (with 700c), upgraded to modern cassette, got new brake calipers (this bike had calipers and needed new one's to reach the rims...also wanted dual pivot), got the Dura-Ace 9 speed bar end shifters, and replaced the rear derailleur with the 9 speed mountain from Nashbar (and works pretty well so far). I made some other little upgrades too, but that was the big stuff and did raise the price a good bit. I kept the crank (and I'd probably keep yours if it is otherwise in good shape and only needs a new ring) and front derailleur. No issues having an old crank and new parts in back. I'm not sure how switching from 27" to 700c wheels, for you, would affect braking if the bike comes with cantilever brakes. I wonder if some models would be adjustable for you with that. Hanging on the 27" rims, for the sake of holding on the 27" wheels, wouldn't appeal to me if I could get out of it some way. I would think the LX hub (modern mountain bike) would be a bit wide for the frame. Especially at your wife's weight, I'd not give any thought to using a modern road hub (130mm) which can be squeezed in there without issue or you can have the frame cold set accordingly.

Can I ask why you changed out the cup/cone bottom bracket with a cartridge??

Seems that if the cups/cones are in good shape, that these older bottom brackets are just as good (and more adjustable?)??

Personally, I agree... conventional BB's are just as good durability wise, as long as you stay on top of the adjustments. On the other hand,
the selection of conventional BB spindles have decreased as the years go by so having a spare or two is always a good thing.

Cartridge BB's are definitely easier to install and maintain. When one goes South, just file it in the Circular File and buy a new one. Plus, they're
much more compatible with newer technology (8/9/10s drive trains).

:speedy:

Hafta chime in here, since I recently built up a 1983 Trek 620 with a modern drivetrain.

I went for the expensive route, Shimano 105 10 speed throughout. 105 hubs are spaced at 130mm and plenty durable. No problem getting them in, just spread the dropouts a bit. Modern Shimano bar-cons are excellent, running either indexed or friction for the rear and friction in front. Must be mated with an appropriate rear derailleur. I run a modern 24/34/48 crank with a Shimano 105 front derailleur shifting butter smooth.

For a more thrifty setup I agree with oldskoolwrench'srecommendation - switch to friction bar-end shifters and maybe replace the chainrings. Indexed shifting complicates everything - shifter has to mated rear derailleur, often requiring a modern cassette and thus new hubs. Dia-Compe makes some nice bar-end shifters, or you can use Shimano SL-BS78 or similar (just make sure they can be switched to friction, the newest SL-BS79 has only indexed for the rear) or then again, you can find some Suntour bar-cons on eBay.

Attached is why a 27" --> 700c compromises braking I think. Sure, the canti's reach. But check out both the pad angle (which would eventually grind down to be flush) but also the angle of the arm.

Thus for this bike, I'll stick with 27" wheels and hope that there will continue to be some options for replacement rims/tires. If I need to switch to 700cc wheels, then perhaps some V brakes might work...or one of those internal hub/brake systems.
http://bikeforums.net/attachment.php...hmentid=269807

I like plan 1. It's very similar to how I have one of my bikes at the moment, the one that gets 95% of my riding time. Dura-ace 9speed bar ends are definitely a good way to go, you get a lot included for the price (cables, cable stops etc.). I wasted money trying to buy less expensive Sunrace shifters, they do not compare.

28/45/50 is a fine setup, and it's probably paired with a 13/16/20/24/28 cogset. I'd leave it the way it is, and get barcon shifters. The problem with chaindrop is technique. Dithering on the shift doesn't help, it requires one to move with purpose. But just for giggles, let's see what happens when we take a look at what you've got here: On the left is the current setup, on the right is your Option 1.

http://www.kstoerz.com/gearcalc/comp...36,48&ighid2=1


You really don't gain much more range with the 3x9, almost nothing on the bottom and a little more up top. You do split up the area where you spend most of your time into finer steps, and that's fine; but it's not laid out with any sort of logic, and there's a lot of duplicate or near-duplicate gearing. To me, the great value of half-step plus bailout is that you know where that next step up or down is.

On my Trek 616, I have much the same setup as yours, with 30/45/48 and an 8-speed rear, as described on the left, below:
http://www.kstoerz.com/gearcalc/comp...s2=28&ighid2=1


Nice, tight half-step, even jumps through the gears. Very predictable. I suppose I could run this as a wide-range double with 28/52, but I really do like the half-step that much, even if I don't do enough touring to really justify it. SO, my advice to you would be to install a set of bar-cons, and if the chaindrop problems persist, something like a Suntour Mounttech front mech, or a Shimano 105 triple front. Cheap and easy, which is nothing to sneeze at. If you want to tighten up the gearing, re-dish and re-space the wheel and install a 13/15/17/20/24/28 six-speed freewheel, which are common as crabgrass.

I bought the bike used and the BB was in a little rougher shape than I like, so I just put in a new cartridge. If it wasn't, I just would've overhauled the existing BB. I did have to use a spacer to get the chain line right and what not.

On another topic of discussion, when I got the dura-ace bar ends (9 speed), I also found that new set came with lots of odds 'n ends that came in useful. Aside from cables, it had a step-down ferrule that fit well into the chainstay cable stop on this old trek. It also came with the adjustable down tube cable stops which, on their own, still cost some money. That was nice.