The Brompton Superlight bikes are some of the lightest folding bikes on the market today. They are easy to recognise as their model numbers are suffixed with -X, so for example the superlight version of the Brompton M3L is the M3L-X. You will also notice that the decals on the frame are different, oval rather than rectangle shaped.
The lightweight is achieved by using specially designed Brompton titanium parts. The Brompton titanium bikes still use the main steel frame but they have a lightweight Brompton titanium rear frame, forks, pedal axle bolt, seat post and mudguard stays. The titanium bikes have also got an upgraded alloy head set. These bikes aren’t cheap, but if you want a sturdy, reliable and lightweight folding bike your search stops right here.
You need to be aware that quite a few parts are specific to these bikes, for example if you are replacing the wheels, you will need to make sure you get the Brompton superlight front wheel. I’m not actually totally sure what the difference is, so if anyone wants to enlighten me, please let me know.
The weight difference between the superlights and the fully kitted out models gives a weight range from a sleek 12.5kg right down to a superlight 9kg. There is a compromise between the number of gears and weight – the less gears, the lighter, as you would expect. Only those living on the flattest terrain would opt for the single speed bikes, the best compromise being the 2 speed derailleur option. The lightest handlebars are the more straight S type handlebars, which are lower than the M type handlebars. The L in the model number always means that this is the light version with no rack, but does have mudguards. You can go for no mudguards which is the E version, but if you live in the UK you know that this makes no sense. This means that the most popular superlight in the UK is the Brompton S2L-X, which only weighs 9.8kg. The Brompton S1E-X weighs only 9kg, but you may get sprayed with mud and find hills a bit tricky.
Out of all the Brompton folding bikes the -X range is the most desirable and the most expensive, but if you can afford one you will love it.