bikemig 

One of the neat things about the '79 510 is that the rear triangle is set at 123 so you can run a 120 or a 126 OLD wheel. That sort of in-between rear triangle is not uncommon (128 is pretty common so you can go 126 or 130).

The frame was built for 700c wheels but there is plenty of clearance for a 27 inch wheelset with 27 x 1 and 1/4 tires as well. I have a good set of 27 inch 120 OLD wheels on hand with Sun CR 18 rims and Shimano 333 hi flange hubs that needed a home. Yesterday I overhauled the hubs and trued the wheels. I liked the idea of running shimano hubs on this build as I put together a mixed shimano FC 6200/6207 group (brakes, derailleurs, and crank) for the build.

The crank has 52/39 rings. I found a funky and very lightly used 5 speed suntour winner pro freewheel with 15-18-20-23-27 cogs. The gear ratios aren't half bad with 52/39 rings. Not much of a top gear but I don't care. The in-between gears are decent and I can use the low when climbing the few 10% grades in Des Moines. This gives me 8 usable gears with a 94 inch high and a 39 inch low gear.

mountaindave 

That is indeed a funky FW, especially with the 15-18 jump. But if this is just a knockabout bike, it shouldn’t be an issue and I can’t imagine needing any more gear inches on either end. Looks perfect.

bikemig 

I installed a Shimano FC 6207 headset yesterday. The star lobed design looks cool in a jet age kind of way but it's a bit of a PITA to adjust. I also sprayed the inside of the frame with Weigle's frame saver, used clear nail polish to deal with the missing paint, and waxed the frame. So it's time to actually built the bike.

I managed to piece together a Shimano group with mixed FC 6200 and 6207 parts other than the pedals which will be MKS Lambda pedals. They're good pedals for running around town. The headset, shifters, and rear derailleur are FC 6207; the rest of the parts are FC 6200. The hubs are hi flange Shimano 333. There's something neat about a pure parts bin build with no cash outlay.

tkamd73 

The wheels on my 77 900 are 27 inch, no issues. I think the frame looks better with a slightly bigger wheel. Tires are Continental Supersports 27 x 1 1/8in, but plenty of room for 1 1/4 in tires.
Tim

bikemig 

This bike is beautiful. Yeah one of the things I like about 70s era racing bike is that they generally took "standard" reach brakes which means that you can likely fit a 27 inch wheel or a little fatter tire (say a 32c if sticking with 700c).

My 510 is more of a "touring" model but the differences between racing and touring bikes were generally not as great in the 70s as they would later become.

c0rbin9

This is so nice, I love vintage Treks.

c0rbin9

I just missed a mid 80s 520 or 620 that was on Facebook marketplace disassembled but complete as "Trek bike". It was listed for, wait for it, $50.

bikemig 

Work got in the way of this build but I finally finished it. I really like how the bike came out.

(1) I put the fattest tires this bike can manage, 700 x 35c Schwalbe marathon racer tires, so I can ride this on gravel as well as pavement. The rims--superchampion 58s--are perhaps my favorite vintage clincher rims. They build up great and hold their true. I rode a set of these on a cross country tour and they are still straight. The hubs are campy tipo low flange.
(2) The brakes are long reach Shimano BR 1050s. The calipers are cane creek. I like having a quick release on the caliper and the brake when running a fat tire. With 2 quick releases, I can get the wheel out easily with the tire fully inflated.
(3) The bike is running perhaps my favorite suntour derailleurs: the suntour VX GT RD 2400, suntour mountech front derailleur, and suntour LD 1500 shifters. These are such good shifters. The gearing on the bike is pushing the capacity on the rear derailleur (velobase has the chain wrap as 34) but it works. The chain is a little looser than I like on the small/small and rear derailleur is splayed out on the large/large but the current chain wrap is 38 which is larger than the RD is rated for.
(4) The crank is a sugino AT with 50/38/26 rings and a 14-28 shimano 6 speed freewheel. I like a really wide ranging gearing so I can ride the bike over any terrain. The gears run from a high of 97 inches to a low of 25.2 inches.
(5) Shimano 600 EX headset. Good headset with the funky locknuts. I used the bar (sakae), stem (SR royal), and seatpost (a campy aero design) on a cross country bike tour so they suit me fine. I like the avocet racing one saddle but I wouldn't mind tracking down an avocet II touring saddle for this bike. Pedals are MKS lambda. I like them a lot. They work great with any shoes that I happen to be wearing.

The paint job is in very good shape. The Imron paint jobs on old Treks are tough. Vintage Treks had a lot of plain color schemes but that's part of their charm. I like all shiny aluminum bits on a vintage bike. They look right and make the bike color pop.

SJX426 

bikemig Great build! thanks for sharing!
When did Trek move from low temp silver to Brass brazing? I have a 1984 610 with brass.
P1000865, on Flickr

bikemig 

I don't know when Trek moved away from low temp silver brazing. I know my '79 Trek 510 is low temp silver brazed as this how Trek built bikes in the late 70s (at least the better ones). I'll bet JohnDThompson knows the answer though.

The '84 610 is a really fine bike. I own one but the 510 is replacing it so I'll be selling it once I rebuild it.

canopus 

Remembrance being fickle.. Trek started to move away from hand/silver brazing around '79/'80 I believe, depending on the model. They had to start modernizing and using automated processes to keep up with sales. And they started using their own cast lugs in the early '80's so the tubes could be cut square and they didn't have to spend so much time on tube fitting.

Take a pick of your '84 head tube and it should be an example of a full cast head tube. The only thing I believe that is brazed is the top and down tubes, the full head tube and lugs should be cast together.

bikemig 

I took it out on the first test ride around 15 miles with some climbing (or at least what passes for climbing in central Iowa, . The paint has a nice sparkle to it which didn't show up in the first set of pics because of the lack of sun. Plus I know I'll swap out those pedals for a set of platform pedals. I have a set of Silstar SP 11s that will look right on this bike. With the MKS deep cage, I'll be able to run ordinary shoes when I want. I like platforms for commuting and kicking around town but I want something with a more positive shoe engagement when riding hard.

adam.schwartz4

bikemig how you like them Shikoros?

bikemig 

I ended up using Schwalbe Marathon Racer 700 x 35c tires as my favorite ride has a longish gravel section and I wanted to run little wider tire than the Shikoros (which measure 32c).

Road Fan

Great project! I like parts bin builds, but I find it's like dieting - don't ever look at the candy or chips! Before you know it you may click BIN for some mint Campy 8-speed levers with hubset, and then ... you're off the wagon!

Seroously, yes many builders went to a bigger tube gauge for bigger frames, but never mind Trek did that for the DTs on its Reynolds 531 frames. My 1982 53 cm c-t 720 has the 0.7 mm DT, based on measuring through the bottle rack mounting hole. But did they generally increase gauge for the larger Ishiwata frames, say in the TT?

Plus, if you have any rings or such for a 86 mm Apex chainset, I could use a little more variety for the one on my 1984 Trek 610 (bought new, but now is a parts box bike).

bikemig 

I like the 1984 610. The 510 I just built replaced my 610 that I'll need to sell. The two bikes are pretty close in terms of quality and functionality but I decided to keep the 510.

I built this bike up with 110/74 bcd crank, not an 86 bcd crank. Are you running an SR apex 86 bcd crank on your 610? You can pick up new chain rings from Spa cycles in the UK but the shipping has gone crazy high because of the pandemic. I have had good luck finding what I need on eBay at decent prices as there are so many of these chainrings floating around.

Road Fan

For 110/74 so many different chainsets were designed and sold, that I think the parts supply will outlast us. But I did find a few 86 mm parts. I also found a full Stronglight chainset in that configuration and I'd like another - it looks really nice! I have two friction builds coming up. One will be a Woodrup Giro and the other will be the 1982 Trek 720 that will replace my 610.

bikemig 

I built this bike two years ago. It has become one of my favorite bikes. I've never worried about weight on a bike as I figure if the bike is built right, it weighs what it needs to weigh. That said, this bike weights 25 lbs with a rack; 24 without. Plus I'm running a triple and the Schwalbe marathon "racer" tires and superchampion 58s (my favorite vintage rim) which are not lightweight.

I recently bought a Wahoo Element Boalt (vers 2) which I've been enjoying using on the bike. Looking at my times reminds me of how fast I used to be (or at least how fast I like to think I used to be!) . Plus the computer cost 2x the price of the bike so there's that.

I took it on my favorite local ride, a twisty and surprisingly hilly (at least for central IA) route with plenty of water views and good tree cover. The gearing is perfect since I don't need anthing below a 38/24 or maybe a 26 for the local climbs. With the 700 x 35c tires, the bike handles the rough spots on the path very well. The bike feels great when you lean it in a curve and it tracks great. Plus I have the fitting dialed in. I really should do something about those bmx style pedals (MKS Lambda) but I've been riding them for 2 years so this clearly hasn't been a priority,

mountaindave 

Lambdas are what I ride on the majority of my road-ish bikes. I'd say if it ain't broke...