How to identify a steel bicycle frame

Over the years bicycle frames have been constructed from a vast array of materials such as;

  • steel
  • aluminium
  • carbon fibre
  • timber (and who knows what else)

This short article has been written to help identify if the tubing in a frame is made from steel as the paint can sometimes make it hard to tell the material used in the frame. This is particularly useful when trying to identify the model of a vintage bike.

All you need to do is place a magnet onto the tube. If the magnet is firmly attracted to the tube, it is made from steel. Whilst a magnet can still be attracted to titanium, it will not be a strong bond like you get with steel. If there is no attraction, then the tube will be made of something other than steel, generally aluminium or carbon.

If you are worried about scratching the paint, you can put a bit of electrical tape or cloth around the magnet. No need to drag it over the tube, simply place it onto each tube you want to test.

Note: There are some ‘Frankenbikes’ out there that have a mix of tubes made from different materials, so it may pay to check each tube in the frame if you want to be really sure the whole bike is made from steel.