Buying a secondhand steel frame? Read This First

Thinking of buying a secondhand steel frame?  Want to avoid some of the pitfalls?  Not sure where to start?  Perhaps your thinking of building a bike up to take part in L’Eroica? 

Is your secondhand steel frame for a period restoration or modern conversion?


The most important question you should answer before even looking at a frame is what are you going to use it for.  If your planning on restoring a frame and fitting period equipment then in some ways its more straight forward.  However if you’re wanting a modern bike built around a classic frame then there are plenty of things you need to consider before hand.  If your planning on converting an old frame for new equipment then a 1950s frame is definitely not going to be suitable.

In this post we’ll concentrate on choosing a frame for a period restoration.  We’ll look at conversions in a later post.

So what do I need to look for when buying a frame?

renovations and resprays waiting to go to the paintshop
renovations and resprays waiting to go to the paintshop

Just like when buying a house or a car or whatever, when buying a bike its best not to be ruled by your heart.  If a frame has a lot of problems it could soon eat a whole in your wallet.  Sometimes its better to walk away.

Here’s my top 10 things to check when buying a secondhand steel frame

1 Are there any signs of crash damage?

both the top and down tube are bent on this Mercian, also no forks sugest that they are also damaged.
both the top and down tube are bent on this Mercian, also no forks sugest that they are also damaged.

It’s very common to see steel frames which have crash damage which isn’t that obvious if you don’t know what to look for or sometimes feel for…

Does the frame come with forks?  Always be wary if no forks come with the frame as this is a possible sign that the frame has had a front end impact.  If it doesn have forks, make sure they match the frame.  There will usually be a frame number on the fork column as well as the frame, so they should match.

Check the obvious, you need to check the frame visually from a side perspective and a front perspective.  Are any of the tubes bent or bowed? Do the rear dropouts look to be in line with the frame.

It’s also handy if you have a wheel to hand which you know is straight and dished properly because if it doesn’t sit in the frame properly with an equal gap on each side between the rim and the chainstays and seatstays then there is something up.

If you can’t see any problem with the top and down tube, you should still run your fingers under the tube, just behind the head tube to feel for any ripples.  Any ripples would suggest the frame had a front end impact.

When checking the forks you need to check them from the side view to see if the fork column is inline with the fork blades and then from the top angle to see if either of the blades is bent.

2 Is the frame in track, is it straight?  Has the rear end been opened up?

Fitting a 130mm rear hub in a frame built for 126mm or less will usually lead to the frame being out of track.  There are many crude ways in which frames have been opened up over the years to take more modern wheels and nearly all of them result in the dropouts being misaligned in relation to the rest of the frame.

The best way to check dropout alignment is with string, although it does rely on the rest of the frame being straight.

3 Does the frame have a stuck seatpost or stem?

Not difficult to have sorted out if there is a stuck item. Just check if a previous owner has tried to remove it themselves which often can cause damage to the frame, making a repair more costly.

4 Do the headset cups just fall out of the frame with very little persuasion?

Headset cups should be a tight fit, if the old cups fall out then the frame is going to need some work to correct this problem.  Not mega expensive, but you don’t want to find this out when the frame has been resprayed!  Also look out for bodges such as coca cola can shims wrapped round the headset cups.

If the frame you’re looking at doesn’t have a headset fitted, take some good quality steel cups with you to check.

5 Are the fork column threads in good condition?

Make sure the fork column threads are in good condition
Make sure the fork column threads are in good condition

Make sure the threads are in good condition on the fork column.  They can be checked visually, they should be uniform and all of the same height.  If there is a bulge in the steerer, this can be a sign that the stem has been over tightened.

6 Are the bottom bracket threads worn?  Have oversized bottom bracket cups been fitted at some point?

Check the bottom bracket threads with some good quality cups, there shouldn't be lots of side to side play
Check the bottom bracket threads with some good quality cups, there shouldn’t be lots of side to side play

Another common problem with old frames is that the bottom bracket threads have become worn.  Usually this happens because the bike has been ridden with a loose bottom bracket.

If the frame has a bottom bracket fitted, fist check if it has oversized cups fitted.  These will look quite plain and have an “O” stamped in them.  If a standard bottom bracket is fitted, undo the cups a few turns and see if there is any side to side play.  The cups shouldn’t rock from side to side, if they do the frame will probably need a new bottom bracket shell.

7 Are the rear dropouts in good condition?  Are the end adjusters stuck?

Make sure the rear dropouts are in good condition.  The dropout slots should be parallel to each other and the rear derailleur hanger should be inline vertically.  Check also that if the frame has end adjuster that they both turn freely, if they are seized in they can be difficult to remove.  If the frame doesn’t have end adjusters fitted, make sure that the holes where they should go are not blocked by an old one which has been broken off.

8 Are the any large dents which can’t be filled?

A dent like this probably requires a new tube fitting
A dent like this probably requires a new tube fitting

If a dent is large enough that the tube is no longer round then this may mean replacing the whole tube rather than just filling the dent.

Pay particular attention to where any front derailleur has been clamped as it is common for them to be over tightened, which crimps the seat tube.

9 If there is chrome plating, is it in good condition?

Chrome can be a headache on old frames as it is difficult to paint over, but i becomes even more difficult if the chrome has started to rust and in extreme cases flake off.

First of all clean the chrome up with some metal polish, if it cleans up nicely then it can masked during the painting process.  Otherwise if you don’t want to save the chrome it can be painted over, however if there is pitting then this will show through the paintwork when the job is finished.  If the chrome has started flaking off and it’s really beyond saving then it needs to be removed.

Removal of chrome plating usually means sending the frame to the chrome platers, so they can reverse the process.

10 If there is rust, is it just on the surface or has it eaten into the metal?

Rust sometimes looks worse than it really is but then other times its eaten into the metal itself.  All you can really do is remove as much rust as you can with some wire wool. You should then be able to see if it’s just on the surface or whether it goes deeper into the metal.  Rust on the lugs and chanstays is less of a problem than on one of the main tubes.  The main tubes on a lightweight steel frame are less than 1mm thick in the middle, so you need to be careful if the main tubes have more than just surface rust.

and finally I know I said 10 but here’s another

11 Has there been any bodge repairs or additions?

Over the years we have seen hundreds of bodges, so if it doesn’t look right it probably isn’t.

This list isn’t exhaustive

But we have covered most of the common pitfalls.  However if you bring or send your frame to us then we will be able to advice you further.

Get in touch

If you want us to help with any part of your rebuild or renovation you can email us at