Trek 520 refresh and update.
 

I picked up a '87 Trek 520, that I have mentioned in a few posts lately, and am in the process of freshening it up a bit. I'll post the details here, to sorta keep all my enthusing confined to one spot. I am pretty happy about my new old bike.

So. Back in the day....... In 1983 I was stationed at NAS Miramar in San Diego (wicked good duty, btw), and while all my shipmates were dropping all their cash (we didn't make much) on cars, I figured the cheapest way to have good transportation (so I could live off base) was to get a bike. So I picked up a brand new Trek 640. Gorgeous bike and not really well known in SD at the time. Rode the living hell outa that thing. So I moved off base and my shop Chief is quizzing me on how this bike-only approach will work. "What cha gonna do in the winter?" I almost laughed out loud. I am from Iowa. I was in San Diego. Winter is like 50 and drizzle there. I assured him I would be OK.

So always had a soft spot for Wisconsin made Treks. Been looking around for one for a while, but man have they gotten pricey. Last year on RAGBRAI I ran into a guy that was riding a perfectly restored 640. Now I REALLY wanted to get serious about an old steel Trek. Had to be in decent shape, 531 tubing, touring format (I am a 54 year old Clydesdale) and '85 or later so as to get the fancy lugs that have the seat stays integrated into the top lug. But, like I say, those have gotten pricey ( a grand + for a good 720? really?).

So a month ago I found a nice '87 520 on eBay (meh), in what looked to be really good shape, and interestingly enough wasn't getting cray attention.

http://i1098.photobucket.com/albums/...psri4qm4nm.jpg

So, got the bike, looked it over and it is in REALLY good shape. Like catalog good shape. This thing has spent a lot of time in the garage. Put about a hundred miles on it. I had expected to do a lot more work (read: Upgrades!!), but I think this is going to be substantially stock, with one big exception. I have become a big fan of STI brifters.

So, step one, strip it down, fix the paint and re-grease it up.

http://i1098.photobucket.com/albums/...pseceyzdxy.jpg

It really only has 2 big raw spots, the look like rub spots from moving maybe. Picked up some matched paint pens, and fixing these now.

http://i1098.photobucket.com/albums/...pszdldjdaj.jpg
http://i1098.photobucket.com/albums/...pszf4tg9ff.jpg

Also measured out the BB for a new sealed unit, it is 121mm, Velobase agrees with that, but suggested a 127.5mm UM54 sealed BB. I ended up getting a 127mm UM55, but am now wondering why the extra 6mm? Wouldn't a 122 be a better, more correct fit for a Shimano B124 crankset?

You can probably go lower than 121, maybe down to a 118, if you can go smaller width it should improve your chain line, take a photo for us if you can of the relation distance wise of smallest chain ring to frame, if with the original BB you have a gap of around 5 mm between chain ring and frame you can indeed go down to a 118, this will improve the life of you chain somewhat.
I would never go to 127.5 on a road or touring bike.

You can see how it's offset in the first pic.

http://i1098.photobucket.com/albums/...ps4enui6l0.jpg
http://i1098.photobucket.com/albums/...pskafbatqk.jpg
http://i1098.photobucket.com/albums/...psvkhqv3sf.jpg

I personally would try a 118( maybe get a wrecked 2nd hand one from a Co op as a sizing tool) you seem to have the room, and I imagine your chain line will be better.
122.5 was the rule with triple Shimano crank sets laid out by the factory but I feel this was only to avoid compatibility issues manufacturer to manufacturer with a variation in chain stay angles and shape.
Someone else should pipe in soon and either support my view or very nicely blow it out of the water. :thumb:

That's a beautiful bike. Great paint and frame work.

I'll back you up, if that last photo shows the crank snugged down, then it's way too far out there. Just looking at the huge gap between the small chain ring and the chain stay tells the story.

Those picture show the original 121mm, offset BB, the crank is snugged down tight.

Yep 118 should work beautifully, a lot of people don't know that you only need about 2mm clearance between chain stay and chain ring, providing your smallest ring is straight that is.
Beautiful bike mate, look forward to seeing pics of it post first ride.

Back at my project. Upgraded the stock 6 speed freewheel to a TZ21 7 speed freewheel, both are 14-28, so not picking up any range. But it will allow me to keep the stock Deore derailleur and add in a set of MicroShift 3x7 brifters, so that will be fun.

With the new freewheel on, I lined up the triple front on the stock BB and the new 7 speed, and I think I am going to go with a non-offset, Shimano UN55 in 68x 122.5 instead of the 68x127.5 I expect this to pull the drive side in just under 2mm, and add just over 3mm to the non drive side.

Back to paint and clearcoat....

Love the bike; good job. I've had good luck finding vintage Treks in IA including a 1978 TX 900, a 1979 510, a 1982 720, and a 1984 610. Keep your eyes peeled on your local CL and things will pop up if your patient. I really like old Treks as well. 127 mm BB is not that unusual for a triple crank (that's what I use with some shimano triples as that is what they came with) but if you can go smaller, that's better.

There are a lot of that vintage Treks around here. Unfortunately I have either been 15 minutes too late, or they are the wrong size or complete basket cases. I may take a swing at a basket case after this one is done...

OK, FrameSaver is messy and makes my house smell. I'll be glad to be done with that part, cuz all my pieces/parts are here and all I need to spray on some clearcoat.

Hopefully riding by this weekend. On this bike.

I am almost sure I used a 122.5 cartridge on my '87 520, and the chainring nuts were ticking on the BB lugs. I wound up having to add a couple 1mm shims. But maybe your bolts are slightly different or whatever. If it works, good.

Well, as it turns out, I had that exact issue just now. I had a 127 BB on the bench as well, so I just swapped the 122 out and the 127 in. Chalk one up for Velobase and Sheldon on that one.

http://i1098.photobucket.com/albums/...pskggvsbur.jpg

So, reassembly is underway, with the intention to be getting miles this weekend. The paint pen I ordered was less than impressive, and a poor color match, but the steel is protected, so....

Shout out to @ThermionicScott for the 7 speed freewheel, it looks good on there and should just clear.

http://i1098.photobucket.com/albums/...psafvlibrw.jpg

New stem, quill adapter, cowbell 3 bars and MicroShift 3x7 are loose fit on there and I am digging the way this is coming together.

More to follow.

The 520 Cirrus is a great riding frame. It is my utility bike this summer and it rolls up the miles quietly and quickly. I am surprised the 25mm tires on it are as smooth riding as they are.

Wonderful!

Speaking of tire width, any thoughts on how wide of a tire this frame can take?

With 27" or 700c?

I have 700c x 32mm + fenders on mine and there is still room. Guessing 700 x 38 without fenders would not be a problem.

Were you able to keep the factory brakes on yours? Or did you have 700c to begin with?

I am on 27's now, will be for a while but there is a 700c conversion somewhere in the future. Perhaps I'll do a test fit tonight and see how that all lines up with my stock setup.

Neat project and a good chance you're going enjoy the ride.

Have an identical but built with a mix of earlier to slightly newer components of the '87 era. Also running 700x35c tightly fitted under mudguards + f/r racks.

For touch-up paint, I used Dupli-color / Toyota color matched and what D-color calls antique sage pearl BTY1605. Rattle can sprayed into a small cup, mix and then let it sit for a minute before use. Have to allow the hardener to set in for brush work and with metallic, it needs to blend.

I need to update pics of it but basically using an SR Apex triple, Suntour Cyclone derailleurs, Suntour (Schwinn labeled) bar-ends, Shimano Mega-range freewheel 7 speed 13 to 34T. No frame mods needed.

Brakes are Gran Aero-compe, pulling early Dia-compe 980 type canti's with Suntour Power Hangers front and rear. Screw modern disc, I love this simple mechanical lightweight and light finger pull, zero drag set-up. It hauls down effortless even with loads. How it handles heat dissipation might be the only downside, but it won't warp like disc either. If anything, I may attach long ally heat sinks to the pad holders.

Tange Levin headset, SR forged stem, SR drops with Spenco thin pad and then top wrapped with Newbaums. Early Dura Ace seat post. Still trying out different saddles, nothing definite. Fitted a third water bottle cage under the bottom bracket / downtube.

Overall, I'm most pleased with this model. A beautiful solid rider especially when weighted down with gear. Have enough chainstay length for pannier's and easily chugs up climbs. I'm really amazed what the '87 frameset delivers and especially for those in the market for duty level touring. Bargain to be had.

Stock brakes, no issues at all. Here's mine. Goofy paint concept but I really like the bike.
http://i1182.photobucket.com/albums/...psvkky56s1.jpg

That paint is in fantastic shape, and I bet the result will be really nice.

I have a 1986 Elance 310 I did over with a full Shimano 105 (5800) group + 700c wheel conversion:

http://i1238.photobucket.com/albums/...psjmylu6gg.jpg

My starting point was a lot rougher than yours.

Trek is now the biggest bike company in the world, so it doesn't have cachet for me any more, but yes, the Wisconsin built ones are really fine machines. Those folks came into the industry and knew what was needed. They were well conceived and well built, and they were even well priced. The 520 was a well needed design, and I wish there were more bikes like it. Good work here! I would make the same updates you're making.

I really dig these 87 520s. I was really lukewarm on the concept of the 80s 520s- actually until I started looking at, I believe, due ruote's 520. That's such a beautiful bike:


I haven't done a whole lot of comparing the geometries of the 520, 720 and the Voyageurs- but the 520 looks to be built with a great selection of great parts that not only give a bang for the buck, but also look fantastic.

^Thank you. They are great all-rounders. A case could be made that it's really the only bike I need, but you didn't hear that from me.