Classic & Vintage - What to look for in a frame?

My beloved singlespeed (a circa-1978 Raleigh Grand Prix conversion) has just met an untimely end -- I took it in to the bike shop last night to investigate a loose bottom bracket, and discovered that the threads in the BB shell had stripped out. Surprisingly, the bike is still rideable, but it's clearly time for a new frame.

I bought this bike off Craiglist to be a winter beater, and picked it because it was the first thing I came across with horizontal dropouts that was basically my size. ;-)
But it quickly became my primary ride, so I want to put a little more care into choosing the replacement frame.

I don't know much about vintage bikes. I was pretty happy with the geometry and ride of the Grand Prix (though it was a little on the small side for me), but my understanding is that it was a somewhat lower-end model. So I'll probably be looking for something similar, but perhaps a little nicer. What brands/models should I look for? What should I avoid? Are there any general frame characteristics to pay attention to? (Type of tubing, etc...)

To be clear, I'm looking for a frame only, and will transfer all the parts over from my Grand Prix. I'm fortunate to live near Bikes Not Bombs (http://bikesnotbombs.org/shop.htm), who have tons of old frames and bikes in stock, so I ought to have a decent selection to choose from.

That BB shell can be retapped. A competent framebuilder can do it.

You need to tell us a bit more about what you want, and how you ride, and what you like, looks wise.

In this case I don't think the BB shell can be retapped. The threads aren't just bent or flattened, the material is actually worn away, so there's nothing to make new threads out of. I'd love to be wrong about this, but the mechanics at the shop (who I've found to be trustworthy in the past) didn't think it could be saved.

As for what I'm looking for, basically a road bike with horizontal dropouts. My riding is mostly short-distance commutes (it's 5 miles one way to work), and I tend to go pretty fast. The new frame will be built up as a singlespeed (or possibly fixed-gear), with 700c wheels, drops bars, and fenders. I use a Carradice bag so I don't need rack mounts or clearance for panniers.

I'm not sure how much geometry varies among classic road bikes, but I was pretty happy with the Grand Prix, so ideally I'm looking for something similar to that.

Edit: Oh, and as far as looks go, I'm not too picky, as long as it rides well.

Brass can be set round the edge (don't ask me how they do this), and that can be tapped. You really need a framebuilder, not just a bike shop for this.

Frankly, any good quality steel frame (531 ideally, or SLX) should do you fine. The cheapest would be to buy something from the 80's, and since you're in the States, probably an old Raleigh or Peugeot, or one of the good Japanese bikes is going to be your best bet.

This will fix it:
http://sheldonbrown.com/harris/bottombrackets.html#yst

Twenty bucks! That has to be your cheapest solution. Then you can afford to wait, be picky, and get something REALLY sweet for your next ride

And you're right in Sheldon's back yard!

I have a tall 25 inch Raleigh Grand Prix frame (with fork and bb), located near Hartford, CT. Might you have something to trade?

Twenty bucks! That has to be your cheapest solution. Then you can afford to wait, be picky, and get something REALLY sweet for your next ride

You didn't read the fine print:


Note! Your frame must be modified (chamfered/countersunk) to permit one of these bottom brackets to be installed. This requires an expensive special tool that your local bike shop may or may not have availalble


However, Harris Cyclery is not far from me, and presumably they have the tool, so it's just a question of how much they'll charge for the installation. Unfortunately they're not answering their phone right now.

Still, it's probably going be to cheaper than a new frame, and will get my bike back on the road sooner.

I'm also going to talk to a framebuilder (Peter Mooney, whose shop is literally right down the street from me -- sometimes I think I live in bike shop heaven), but I'm guessing that the cost of going that route will be more than the frame is worth.

Thanks for the advice -- I'll post an update once I figure out what I'm going to do.

can't you retap an english BB to italian if the threads are lost being that it is slightly larger in diameter.. then you can use and english BB with Italian cups.. again you need to go to a frame builder... As for what to looks for.. make sure it is your size... look for a chromoly frame (i suspect your grand prix was 10-20 high tensile or something like this) and of course you will need long drop-outs. Forged (thicker) as opposed to stamped drop-outs are preferred but you will find the stamped ones to be longer and the long horizontal forged drop-out much harder to find. But look anyway, a high end frame from the 70s can have long forged drop-outs with no or few braze-ons which is what you want since you are building an SS or fixed. As sammyboy stated 531 frame and columbus are highly desireable but if you want to use it as a beater than you don't need that nice of a frame and it might make it more of a theft target anyway.

I'm not sure how much geometry varies among classic road bikes, but I was pretty happy with the Grand Prix, so ideally I'm looking for something similar to that.


Elbows,

Here are 2 different takes on it. Sorry for making this more confusing than it needs to be....

The short version imo is that there are 4 basic types of road bikes which can be categorized by their chainstay length:

# Road Racer: approx 41.5 cm
# Audax/Event: between 42 cm and 42.5 cm
# Sport Touring: between 43 cm and 44.5 cm
# Loaded Touring: 45 cm or more

Here's my cut at understanding road frames from a functional, riding point of view.
http://home.comcast.net/~pinnah/dirtbag-bikes/bike-function.html

Here's my cut at understanding the same exact question from a more technical point of view on the geometries:
http://home.comcast.net/~pinnah/dirtbag-bikes/geometry-project.html

I'm not sure what your Grand Prix was like geometry wise. Raliegh didn't document their geometries from I can tell from the old catalogs. If you (or anybody) can point me to Ralieigh frame geometry info, I'll happily add it to the spreadsheet.

For retro-rehabs, I would tend to steer clear of Italian and French bikes. Most US, British and Japanese bikes use the same threading and fitting standards so parts move more easily among those frames. You'll run into no end of parts compatability hassles with French and Italian bikes. Best to leave those to dedicated restorers.

Lastly, I would look for something with 43cm chainstays regardless of pannier carrying or not. You'll get more range in tire sizes that will work.

I just talked to Harris Cyclery about the YST universal bottom brackets. It turns out that they've stopped carrying them because of quality-control problems. The mechanic said that it's a great idea, but they aren't made very well.

Rather than re-tapping the BB shell to Italian threads, he suggests using JB Weld to hold the BB in. He says he's done this before, and it will hold during normal use but can still be removed if necessary. The stuff is < $10 at the hardware store, so I figure it's worth a try. It should at least buy me some time to think about a new frame.

he suggests using JB Weld to hold the BB in. He says he's done this before, and it will hold during normal use but can still be removed if necessary.
Yeah I'd go with the JB weld, it's a good temporary solution. I did it on a stripped bb and its held up for two years so far. Be sure to clean out all of the grease on what's left of your threads to insure a good bond. Use plenty of JB weld on the chainring side only and don't touch the bike for 48 hours. Its a slow setting epoxy and you want to let it cure fully. I found a bike shop that will puddle brass in the bb and tap it for me so I'll do that this winter. Epoxy doesn't like heat so you can remove it using a propane torch.

My beloved singlespeed (a circa-1978 Raleigh Grand Prix conversion) has just met an untimely end -- I took it in to the bike shop last night to investigate a loose bottom bracket, and discovered that the threads in the BB shell had stripped out. Surprisingly, the bike is still rideable, but it's clearly time for a new frame.

I bought this bike off Craiglist to be a winter beater, and picked it because it was the first thing I came across with horizontal dropouts that was basically my size. ;-)
But it quickly became my primary ride, so I want to put a little more care into choosing the replacement frame.

I don't know much about vintage bikes. I was pretty happy with the geometry and ride of the Grand Prix (though it was a little on the small side for me), but my understanding is that it was a somewhat lower-end model. So I'll probably be looking for something similar, but perhaps a little nicer. What brands/models should I look for? What should I avoid? Are there any general frame characteristics to pay attention to? (Type of tubing, etc...)

To be clear, I'm looking for a frame only, and will transfer all the parts over from my Grand Prix. I'm fortunate to live near Bikes Not Bombs (http://bikesnotbombs.org/shop.htm), who have tons of old frames and bikes in stock, so I ought to have a decent selection to choose from.

I can't really say much about whether you can retap, or need a threadless BB or what. If you need a frame, I think looking for a suitable geometry is the most important factor for you. You don't seem hugely concerned by weight, since you have been happy with the Grand Prix, with it's straight guage tubing. I would measure the seat tube length from center of BB to center of top-tube, the chainstay length, and the top tube length. Then look for a frame with the same top-tube and chainstay, and 1 to 2 cm larger in seat tube length. Measure the candidate frames yourself to be sure the numbers are compatible. At the tall end of the suitable range, accuracy will matter, especially if the standover height is reaching your comfort limit.

So you need to get a little metric tape measure at the hardware store, and become a numbers dweeb (welcome to the club!) at the local bike shop.

For a "nicer" frame, look for tubing type labels: Reynolds, Columbus, Tange, Ishiwata, and Vitus. The dropouts are an often-reliable sign of overall quality for vintage steel. Look for forged front and rear dropouts, not stamped as for your GP. Nothing wrong with stamped, it's just an added sign of higher quality. Builders used better parts in higher-end frames.

Frames that look good and have good fittings but have no labels might not be a problem or of lesser quality. A lot of established builders made (and make) frames out of mixed-type tube sets to fine-tune the frame characteristics to the customer's preference, and so could not truthfully put a single-maker frame tube label on the bike. Consider if you're Reynolds, would you sell tubes to a guy who puts Columbus tubing in a frame labelled Reynolds?

You probably could repair the frame, but I think you'd be happier with a better one, IMHO.

Ken

I just talked to Harris Cyclery about the YST universal bottom brackets. It turns out that they've stopped carrying them because of quality-control problems. The mechanic said that it's a great idea, but they aren't made very well.


That's too bad. It is a great idea. I just learned of them a week ago in another forum. So long YST... we hardly knew ye!:cry:

A couple of people have mentioned forged vs. stamped dropouts as a sign of quality to look for. How do you tell the difference from a visual inspection?