jlaw

Good Morning,

I recently acquired a one-owner 1985 Trek 410 - 'scarlet' color according to an original brochure that I found. It is almost completely original with the exception of the brake levers and pedals. It even has what I believe to be the original San Marco 'Laser' seat.

I found this bike locally while searching for my first resto project. What I am interested in doing is setting it up with fenders, 650b wheels, and a crankset/gear cluster that works for me in the hill country where I live - the standard type of rando modification that makes most old and new bikes more user-friendly. I am not dead-set on a modern drive train, but I don't want to regret my choices when riding up the frequent 8 to 12% grades in my area.

There are six issues about which I would like your thoughts:

1.) The dropout spacing on the rear is for a 6 speed - 126mm and if I am going to spend the $$ for 650b wheels I would like the wheels to have a 130mm hub so that they could be used on other 'modern' bikes and give me some modern drive train options. I have watched several frame 'cold-setting' videos and I could handle this myself. However, I feel some sense of duty to the guy I bought the bike from in terms of keeping it original - he was a bit wistful about selling it and the good memories he had of many fun days on this bike. Once I modify the frame will the 126mm Rigida rims and 6 speed freewheel no longer work?

2.) The drivetrain is Campy Triomphe - 52/40 in front with 11-24 in back. I would really prefer a 40/26 in front with perhaps an 11-34 in back. Can I simply leave the BB as is and attach a mountain bike double square taper crankset?

I could probably sell the crankset for what I paid for the bike, but I am inclined to keep all of the items I remove so that if someone (someday) wants all the original equipment with the bike it will still exist.

3) The rear derailleur cable is routed through the chainstay. The frame has a small amount of corrosion and slightly bubbled paint around some of the lugs and the cable braze-ons along the top tube - otherwise it is clean. Should I be concerned about the inside of the chainstay that has the holes in it to accommodate the cable?

4) The brakes are Dia Compe G-500's (side pull?). In order to fit fenders and a different size wheel I will need to replace the brakes. Which brakes would you suggest?

5) The rear dropouts are adjustable and the set screws are currently about 3/8" extended. I'm not sure what these screws are for and what could be gained by adjusting them. Insights?

6) The vintage info. I found for this bike indicates that it has 27" (630) wheels. However, the tires that are mounted are labeled 700x25 and there are no labels on the rims. Will some 700 tires fit on 27" rims? I only care about this because it could be a factor in brake reach for the new brakes.

I liked this bike as soon as I got in it and road the first 100 feet - reminds me of my first god bike, a 1984 Peugeot.

I'm new here and will post some pics when I figure that out.

Thanks for your thoughts and have a great day!

The Golden Boy 

#1: A 1985 Trek will be spaced at 128- a 130 will fit right in. No “cold setting” necessary

#2: 40 is REALLY low for a big ring (IMO). Depending on what crankset you select- you may or may not need a different length BB spindle.

#3: I don’t think I’d be all that worried about it- depending on how rusty it is. You may wish to do an OA bath or Framesaver the frame if it is really rusty.

#4: If you stay with the current wheel size- the DiaCompe 500G brakes are good, nicely finished brakes. However, if you change the tire or wheel size- you may need longer reach brakes.

#5: The dropout adjusters are for changing where the axle sits in the dropout slot- you probably won’t need to adjust them a whole lot.

#6: If your tires are marked 700c- the wheels are 700c. 700c (622) tires will not fit on 27” (630) wheels or vice versa.

bikemig 

Why do you want to do a 65b conversion? They're cool and ideally they let you run fatter tires but it's not an entirely no brainer conversion.

Here are some good guidelines,

650B Conversion Guidlines

jetboy 

#5 with larger rear cogs it can sometimes be advantageous to slide the wheel further back (and up) which gives more distance from the derailleur which can help getting onto that 34t you are trying to sneak on there. you can actually just take the adjuster out and slide to the very rear for if you have to.

you are basically trading a bit of crispness in the smaller cog changes to fit a larger range. not a problem unless you are racing as far as I can tell.

TenGrainBread 

Triomphe is not a particularly rare or desirable groupset, nor is the Trek a particularly rare frame. I would sell the groupset if you want compact/wide range gearing. Keeping the bike riding in a comfortable way is way more important than keeping it original. I think you'll find most here agree.

Tektro R559 brake calipers are the go-to choice for 650b conversions. If you are planning on riding on the brake hoods I would also switch the brake levers to a modern wide-bodied lever. Like a Cane Creek SCR-5 or a nicer TRP lever.

I would move the adjuster screws out so you can put the wheel all the way back in the dropouts. Maximize your wheelbase. It will make the bike slightly more stable.

Put a nice vintage long cage MTB rear derailleur on there to handle a big cassette. If you don't mind going modern, new Shimano and SRAM mtb rear deraulleurs have a clutch spring to hold tension in the chain, minimizing chain slap, drop, and noise. And they can handle a 42t cog in the back! Just be Aware that 10 speed SRAM derailleurs generally require more cable pull than a friction shifter allows, if you are using a 10 speed cassette.

McBTC

Definitely no low gears there but a vintage trek with more OEM Campy stuff than downtube shift levers seems pretty unique... wonder how small an inner ring and how big a freewheel might fit on it.

jlaw

From what I have read the Triomphe groupset was a transitional design for Campy from previous designs that worked for decades but were, by the mid-1980's, being surpassed by the newer Japanese components from Shimano and others. I think Triomphe was only made for a few years. One interesting item is that the RD does not have a B screw.

The BCD for Triomphe is 116mm - unusual. 35T and 36T chainrings can be found online as a substitute for my existing 40T. Pricey, but this is one possibility. Thanks.

jlaw

You make some very good points.

The Tektro 559s are well-reviewed and I do ride the hoods, so a more comfortable lever/hood (than the existing Dia Compe's) will be a plus. I took the bike out for a ride this afternoon. I liked it - light and lively - but the single pivot Dia Compe brakes did not inspire confidence on the downhills.

Moving the adjustment screws out will also allow for a bit more tire clearance between the chain stays.

I have a Deore long cage RD that I'm going to try with the bigger cog configuration.

I also need a longer stem. It was spec'd with a 100mm stem, but the previous owner installed a significantly shorter stem and this feels a little shaky. When looking down I can see the front axle with about 1.5" to spare in front of the stem.

Thanks!

Mooo

I bought one of those new in 84. Also scarlet red. The 85 was basically the same.

It was a fantastically good bicycle, without being the least bit pretentious.

edit: don't underestimate the DC brakes. I've used them in the Appalachians and the Rockies and never felt under-braked. They modulated well and were strong enough to break traction. Unpretentious, but superbly functional, IMO.

jlaw

You are correct! I thought the rear dropout spacing was significantly under-sized because I took the rear wheel from my wife's hybrid and tried to fit it onto the '85 Trek - not realizing the hybrid has a 135 O.L.D. on the rear. I tried the same thing with the rear wheel from my 2007 Roubaix (130 O.L.D.) and with a little finagling it fit into the Trek. No need to mess with the frame. Thank you!

I've got the bike stripped down to the frame - have a few component choices to make and I'll be able to start the re-build - pictures will follow once I am allowed to post photos.

ThermionicScott 

First thought: Can't wait to see pictures.

Second though: All of my 126mm bikes have remained so. 7-speed cassette hubs are "obsolete" but plentiful and long-lasting, so I build up new wheels around them. 7-speed cassettes and appropriate chains are also inexpensive and widely available. Don't feel that you need to stretch your bike to 130mm (or beyond) in order to take advantage of modern cassette hubs, although it's not "wrong" to do either.

Last thought: 650B is wonderful, but conversions are often a "project" involving measurements, tests, frustration, and compromise.

sarhog

jlaw , do you still have this bike? How do you like it? Can you share a couple photos? I just purchased the same bike off the facebook marketplace a few minutes ago, I’m going to pick it up tomorrow in Asheville, NC. Thanks, and happy new year to you!

For everyone else, yes, I’m aware that the thread is nearly 4 years old. Happy new year to each of you a well!
I am NOT a classic/vintage guy….I guess I better get busy becoming one, right?

jlaw

Hello and Happy New Year!

I do still have the bike. Here it is in its original condition - from the Cristophe toe clips to the Blackburn rack and those old-school plastic bottles, I can still smell them in my mind (they wound up cracking due to age) - purchased from the original owner.


I prefer modern brakes, lower gear ratios, bigger tires, modern bars, etc.... so here's what I did with it - a 650b conversion with 10 speed indexed downtube shifters (Shimano 7900), Tektro 559 brakes to reach the smaller diameter rims, 11-32 cassette, 650b wheels using Pacenti Brevet rims -105 hubs and Panaracer Gravel King 38mm file tread tires, 31.8 mm dirt drop bars with a stem adapter, Velo Orange fenders, 39-26 SRAM MTB crankset with GXP bottom bracket, Shimano 10 speed RD, and Shimano Deore XT FD. I switched the seat to a Brooks B17 Imperial Narrow.


It is a 22.5" frame and was fine for me although the amount of seat post and stem adapter showing indicate that I could have used the next size up.

It was my first vintage bike and first 650b conversion. I really enjoy the wrenching and the riding. The bike was a good rider and I could keep up with my friends on their carbon race bikes for the most part - because they are slow like me!

I have since acquired a 1979 Trek 710 in the 24" size and converted it to 650b. The 710 is a bit more 'special' to me than the 410 and my component choices were slightly different. I also found a 1984 and a 1985 Trek 620 - current projects not yet done. Vintage bikes can be a bit addictive.




Your 410 should be a nice bike and a good introduction to vintage. It's a nice lugged Tru Temper Frame. If you can read the serial number on the bottom bracket you can look it up on the vintage Trek website - https://www.vintage-trek.com/SerialNumbers.htm

What do you want to do with it?

Post some pics!

sarhog

Thanks for the reply. I have no idea what i want to do with it, I just saw the ad on a local bike bike market page, in my size, and thought $100 was pretty cheap, so what the hell. I’m driving up to Asheville tomorrow to pick it up, I’ll post some photos this weekend. Thanks for the vintage Trek link.
I have ZERO experience with vintage bikes, other than owning an 80’s era Nishiki (new at the time) when I was stationed in the Philippines.


1986 or 87, at Cubi Point, RP

jlaw

$100 for a good-condition 410 is a bargain. Once you ride it a bit you'll know what you like about it and what you don't. The good news is that many modern bike components will fit a vintage frame/fork without much fuss or special tools.

Classtime 

Step 1: post pics of your new 410. (Drive side and don't forget to ask the seller about the bike's history.)

sarhog

I created a separate thread for it. Trek 410 post