1984 Trek 400 Build
01-13-19, 11:08 PM
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1984 Trek 400 Build
Hi all,
Starting this build thread for a 1984 Trek 400 frame I picked up here from the C&V Sales forum. I know it's not the most sought after model, but it's a stepping stone to my goal of finding a 1979 Trek. I've only worked on newer aluminum and 90's era steel Trek Singletracks, so this will be an experience builder. It's got quite a bit of scratches and some rust, but no dents and it's solid. Since it's just a bare frame I'm thinking resto-custom-mod also since I have a bunch of newer parts. Here's a pic below and you can also see the original ad in the sales forum for more pics.
Original ad thread where I got it from: 1984 TREK 400 frame (56cm c-t-c)
Stay tuned for more...
Starting this build thread for a 1984 Trek 400 frame I picked up here from the C&V Sales forum. I know it's not the most sought after model, but it's a stepping stone to my goal of finding a 1979 Trek. I've only worked on newer aluminum and 90's era steel Trek Singletracks, so this will be an experience builder. It's got quite a bit of scratches and some rust, but no dents and it's solid. Since it's just a bare frame I'm thinking resto-custom-mod also since I have a bunch of newer parts. Here's a pic below and you can also see the original ad in the sales forum for more pics.
Original ad thread where I got it from: 1984 TREK 400 frame (56cm c-t-c)
Stay tuned for more...
Last edited by amerikaner; 01-14-19 at 11:19 PM. Reason: adding link to original ad with more pics
01-13-19, 11:12 PM
#2
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First things first...gotta figure out sizes:
What I do know:
1984 Trek 400 22.5" frame (Pewter with Red/White decals)
126mm Drop out spacing
Since it's a Tange Mangalloy 2001 frame headtube ID should be 30mm following JIS standard
Bottom Bracket is BSA
What I don't know:
Seatpost diameter? Tried a 27.2 and it's too tight a fit
What I do know:
1984 Trek 400 22.5" frame (Pewter with Red/White decals)
126mm Drop out spacing
Since it's a Tange Mangalloy 2001 frame headtube ID should be 30mm following JIS standard
Bottom Bracket is BSA
What I don't know:
Seatpost diameter? Tried a 27.2 and it's too tight a fit
01-14-19, 08:53 AM
#3
Senior Member
I own 3 Trek 400’s. Only one really accepted a 27.2 post willingly. All had straight sides and ears in the clamp area. Just something about the 400’s.
it will make a fine rider.
it will make a fine rider.
01-14-19, 11:35 AM
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Congratulations!
I had an 84 420 and currently have an 86 400 Elance. Regardless of where these sat in Trek’s hierarchy, they’re really excellent bikes. You hear it often said about 70s and 80s Treks: ‘Trek’s entry level was most other companies’ mid level.’
My 86 400 Elance was the first bike I hunted down. I specifically searched for a blue 86 400... It took several months, but I found one, drove 200 miles round trip and paid too much for it- But I got it- built it up gloriously- I still think it’s my most beautiful bike... The only reason I sold my 420 is because it only had one bottle mount (and Junior’s friend needed a quality bike...)
I don’t recall the seat post size. And I’d re-check that dropout spacing- it may be at 128- and that allows you to squeeze in a 130 with no trouble at all.
It’ll definitely be a fun project!
good luck!
I had an 84 420 and currently have an 86 400 Elance. Regardless of where these sat in Trek’s hierarchy, they’re really excellent bikes. You hear it often said about 70s and 80s Treks: ‘Trek’s entry level was most other companies’ mid level.’
My 86 400 Elance was the first bike I hunted down. I specifically searched for a blue 86 400... It took several months, but I found one, drove 200 miles round trip and paid too much for it- But I got it- built it up gloriously- I still think it’s my most beautiful bike... The only reason I sold my 420 is because it only had one bottle mount (and Junior’s friend needed a quality bike...)
I don’t recall the seat post size. And I’d re-check that dropout spacing- it may be at 128- and that allows you to squeeze in a 130 with no trouble at all.
It’ll definitely be a fun project!
good luck!
__________________
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Commence to jigglin’ huh?!?!
"But hey, always love to hear from opinionated amateurs." -says some guy to Mr. Marshall.
Commence to jigglin’ huh?!?!
"But hey, always love to hear from opinionated amateurs." -says some guy to Mr. Marshall.
01-14-19, 12:46 PM
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Congratulations!
I had an 84 420 and currently have an 86 400 Elance. Regardless of where these sat in Trek’s hierarchy, they’re really excellent bikes. You hear it often said about 70s and 80s Treks: ‘Trek’s entry level was most other companies’ mid level.’
My 86 400 Elance was the first bike I hunted down. I specifically searched for a blue 86 400... It took several months, but I found one, drove 200 miles round trip and paid too much for it- But I got it- built it up gloriously- I still think it’s my most beautiful bike... The only reason I sold my 420 is because it only had one bottle mount (and Junior’s friend needed a quality bike...)
I don’t recall the seat post size. And I’d re-check that dropout spacing- it may be at 128- and that allows you to squeeze in a 130 with no trouble at all.
It’ll definitely be a fun project!
good luck!
I had an 84 420 and currently have an 86 400 Elance. Regardless of where these sat in Trek’s hierarchy, they’re really excellent bikes. You hear it often said about 70s and 80s Treks: ‘Trek’s entry level was most other companies’ mid level.’
My 86 400 Elance was the first bike I hunted down. I specifically searched for a blue 86 400... It took several months, but I found one, drove 200 miles round trip and paid too much for it- But I got it- built it up gloriously- I still think it’s my most beautiful bike... The only reason I sold my 420 is because it only had one bottle mount (and Junior’s friend needed a quality bike...)
I don’t recall the seat post size. And I’d re-check that dropout spacing- it may be at 128- and that allows you to squeeze in a 130 with no trouble at all.
It’ll definitely be a fun project!
good luck!
Agreed! Congratulations!
Those are Tange Mangalloy main triangle and either Mangalloy or hi-ten forks and stays, but I’d wager a very nice ride either way. All Treks main tubes were double butted then, and I think it has 43cm chain stays?
I have an ‘84 610 that’s very close to the 400 Elance. The Sports series from Trek in the 80’s are just really amazing bikes-of-all-trade. Stable to commute on, and zippy for the weekends. Have fun with the build and put up some pics!
01-14-19, 03:06 PM
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I’ve got an 86 400 Elance with 531 triangle, and an 88 400t with the True Temper frame. Both take a 27.2 seatpost, great rides, you’ll have no regrets. Measureing the five 27.2 seatposts I have, the diameter varies between 27.13 and 27.28, If it’s not the post original to the bike, try another, assuming it takes a 27.2.
Tim
Tim
01-14-19, 04:46 PM
#7
Full Member
I have an 82 412 that had a non-OE 27.0 post in it when I got it. Likely because poor finishing of the seat tube made the original 27.2 a right fit.
Took it over to to the local co-op and used a reamer, and then a flex home, to clean up the seat tube and bring it back to where it needed to be.
Took it over to to the local co-op and used a reamer, and then a flex home, to clean up the seat tube and bring it back to where it needed to be.
01-14-19, 08:40 PM
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I have an 84 400 triple. 27.2 seat post is a tight fit. I honed mine out, it's still snug but that is how they fit. It's not a highly sought after collectible, But it is a REALLY nice all around rider. It's comfortable, it's fast enough, but not the stiffest bike, makes for a really nice sporty touring bike. Mine has been to RAGBRAI 2 times, Wonderful bike for that kind of riding.
01-14-19, 11:16 PM
#9
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Thanks, I tried cleaning out the seat tube with steel wool attached to a wire with a drill...got it pretty clean. Tried a Bontrager SSR, one from a Trek 930 and a Ritchey Classic and none could go past the split in the seat post. Going to borrow a 26.8 from friend to see if it fits.
Meanwhile, I need to find a headset that is truly 30mm JIS and not ISO 30.2mm. Was hoping to get a Tange one but the ones I'm finding say JIS like the Levin, but the reviews from people who bought them say they are actually 30.2mm with 27mm crown race ID rather than the true JIS 30mm cups and 27mm crown race ID.
So plans right now are to find a seatpost and headset so I can build it up and get the fit right before I do any other touchups or re-paint or even powder coat.
Meanwhile, I need to find a headset that is truly 30mm JIS and not ISO 30.2mm. Was hoping to get a Tange one but the ones I'm finding say JIS like the Levin, but the reviews from people who bought them say they are actually 30.2mm with 27mm crown race ID rather than the true JIS 30mm cups and 27mm crown race ID.
So plans right now are to find a seatpost and headset so I can build it up and get the fit right before I do any other touchups or re-paint or even powder coat.
01-15-19, 12:53 AM
#10
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Still kinda true today...have a 2016 1.1 that I upgraded to full 105 R7000. If anything though these days the entry level seems to skimp on brakes, bottom bracket and crank.
Thanks, dropout spacing is 126.24mm measured with caliper, but 130mm hub fits fine...in fact barely had the spread it and it slipped right in.
Last edited by amerikaner; 01-15-19 at 12:57 AM.
01-15-19, 12:59 AM
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I’ve got an 86 400 Elance with 531 triangle, and an 88 400t with the True Temper frame. Both take a 27.2 seatpost, great rides, you’ll have no regrets. Measureing the five 27.2 seatposts I have, the diameter varies between 27.13 and 27.28, If it’s not the post original to the bike, try another, assuming it takes a 27.2.
Tim
Tim
01-15-19, 08:26 AM
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Last edited by tkamd73; 01-15-19 at 08:31 AM.
01-15-19, 08:56 AM
#13
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Meanwhile, I need to find a headset that is truly 30mm JIS and not ISO 30.2mm. Was hoping to get a Tange one but the ones I'm finding say JIS like the Levin, but the reviews from people who bought them say they are actually 30.2mm with 27mm crown race ID rather than the true JIS 30mm cups and 27mm crown race ID.
.
.
Tange Levin CDS 1 Threaded Headset 27.0 x 30.0 JIS Chrome [6193 or 35496] - $23.00 Velomine.com : Worldwide Bicycle Shop, fixed gear track bike wheelsets campagnolo super record vintage bike
01-15-19, 11:09 AM
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Congratulations!
I had an 84 420 and currently have an 86 400 Elance. Regardless of where these sat in Trek’s hierarchy, they’re really excellent bikes. You hear it often said about 70s and 80s Treks: ‘Trek’s entry level was most other companies’ mid level.’
My 86 400 Elance was the first bike I hunted down. I specifically searched for a blue 86 400... It took several months, but I found one, drove 200 miles round trip and paid too much for it- But I got it- built it up gloriously- I still think it’s my most beautiful bike... The only reason I sold my 420 is because it only had one bottle mount (and Junior’s friend needed a quality bike...)
I don’t recall the seat post size. And I’d re-check that dropout spacing- it may be at 128- and that allows you to squeeze in a 130 with no trouble at all.
It’ll definitely be a fun project!
good luck!
I had an 84 420 and currently have an 86 400 Elance. Regardless of where these sat in Trek’s hierarchy, they’re really excellent bikes. You hear it often said about 70s and 80s Treks: ‘Trek’s entry level was most other companies’ mid level.’
My 86 400 Elance was the first bike I hunted down. I specifically searched for a blue 86 400... It took several months, but I found one, drove 200 miles round trip and paid too much for it- But I got it- built it up gloriously- I still think it’s my most beautiful bike... The only reason I sold my 420 is because it only had one bottle mount (and Junior’s friend needed a quality bike...)
I don’t recall the seat post size. And I’d re-check that dropout spacing- it may be at 128- and that allows you to squeeze in a 130 with no trouble at all.
It’ll definitely be a fun project!
good luck!
01-15-19, 08:15 PM
#15
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Thanks hobbitman...all the other places that carried the Levin had the 30.2mm diameters. So it's this one, the Velo Orange one or find a vintage one on ebay...was hoping to find a sealed bearing one but can't find one in full JIS except for older Dura Ace ones that are super expensive.
01-15-19, 08:59 PM
#16
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I have a 1980 412 and love that bike! mine is Ishiwata 022 main triangle Ishiwata 0265 Hi-Ten forks and stays. I remember a 27.2 post was tight for some odd reason when I bought it, It was kinda tight but it went down, have a Thomson seat post right now in it.
I just switched out the NITTO 90mm stem to a black CINELLI 80mm. Im wanting a little bit more height and thinking I might switch to a NITTO Pearl stem.
I also have a pretty trashed1987 Trek 400 Elance that I'm not sure what to do with yet.
I just switched out the NITTO 90mm stem to a black CINELLI 80mm. Im wanting a little bit more height and thinking I might switch to a NITTO Pearl stem.
I also have a pretty trashed1987 Trek 400 Elance that I'm not sure what to do with yet.
01-15-19, 09:20 PM
#17
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Ooooh...that's nice! The older logo matches so much better than the mid 80's one. Still searching for a '79! As for the seat post, gonna try a 26.8 and if it's too loose. I'll go the honing route...just kina pricy for the tool.
01-15-19, 09:31 PM
#18
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The 27.2 into my 614 is pretty tight. I haven’t installed the new post yet, but I feel like the tube could use a hone.
01-16-19, 07:20 AM
#20
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01-17-19, 03:24 PM
#21
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Just got the seat binder bolt last night. Fits perfectly. Now I just need a seatpost!
Also, here's the fork that came with it. It's not original but it's a Tange. Steerer tube is a bit long, but will see by how much once I get my headset. I did notice one thing though when test fitting a wheel. The spacing is bit narrow...not sure if this is normal or if there was a narrower standard. I did some other measurements and it's straight and square with not dents anything so not sure.
Also, here's the fork that came with it. It's not original but it's a Tange. Steerer tube is a bit long, but will see by how much once I get my headset. I did notice one thing though when test fitting a wheel. The spacing is bit narrow...not sure if this is normal or if there was a narrower standard. I did some other measurements and it's straight and square with not dents anything so not sure.
01-17-19, 07:25 PM
#22
Senior Member
The 400 series has comfortable geometry with a sporty feel. I bought an '85 410 and took it down to frame/fork - kept the headset, seat, and seat post - installed modern components with 650b wheels and fenders - great all-arounder.
Have fun with yours!
Have fun with yours!
01-17-19, 08:18 PM
#23
Senior Member
I also had some serious seat tube issues with a Trek 400 series bike. A few years back I bought a 1984 Trek 420 Cirrus for cheap because of a stuck seat tube. It was a beautiful bike with a Reynolds 531 frame and cantilever brakes. But, it was in rough shape and - the seat tube was stuck. I stripped the bike down to the bare frame and put the seat post in a bench vise. Started twisting the frame back and forth. Decided to either bust the frame or break the post. Fortunately, the post broke free before the frame broke. Sandpapered the post and inside the seat tube. Greased everything up. Put it all back together. No worries since. Still own the bike. One of my favorite rides.
01-18-19, 11:17 AM
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OP, seat posts were made (once upon a time) in diameter increments of 0.2 mm. You could get a seatpost in 27.0 if a 27.2 is too big, and give it a try. You don't really need to worry about it until near the end of the build.
An important early-build issue is matching the frame and fork using the headset.
Your headset has a specification called "stack." This is the combination of the heights of the lower bearing set and the upper bearing set. The lower set is measured from the bottom of the crown race to the bottom of the lower head lug. The upper bearing set is measured from the top of the upper head lug to the top of the fork steer tube. On the bike it should match the steer tube length minus the head tube length. A typical spec is 35 to 42 mm. To a small degree you can fine-tune the fit with spacers or washers under the locknut, but the best solution is a perfect fit. It needs to tighten with no play (there usually is not a torque spec for threaded headset preload), and the locknut needs to engage to as many threads as possible for strength and durability.
Not a huge issue to make it right but it deserves to be done right.
An important early-build issue is matching the frame and fork using the headset.
Your headset has a specification called "stack." This is the combination of the heights of the lower bearing set and the upper bearing set. The lower set is measured from the bottom of the crown race to the bottom of the lower head lug. The upper bearing set is measured from the top of the upper head lug to the top of the fork steer tube. On the bike it should match the steer tube length minus the head tube length. A typical spec is 35 to 42 mm. To a small degree you can fine-tune the fit with spacers or washers under the locknut, but the best solution is a perfect fit. It needs to tighten with no play (there usually is not a torque spec for threaded headset preload), and the locknut needs to engage to as many threads as possible for strength and durability.
Not a huge issue to make it right but it deserves to be done right.