There are key parts of amazing things that are made in Rotherham – Rolls-Royce engines, Stanley knives, McLaren supercars. Here’s one more to add to the list – Brompton bikes.
Brompton Bicycle, a British manufacturer of iconic folding bicycles has launched its lightest bike ever, and it has been made possible by CW Fletcher, a precision engineering firm based in Rotherham.
CW Fletcher supplies a diverse range of industries, including aerospace, nuclear and space exploration. Its “Sterling Works” is part of a 9.5-acre combined site located at Wales Bar in Rotherham where high-strength, lightweight assemblies in ordinary and exotic metallic materials are fabricated and high value-added components are machined.
The precision engineers told Brompton that their folding bike could be made in titanium when others said it couldn’t.
The product of three years of research and development, Brompton has brought its fold to life in titanium by forging new construction techniques, designing over 150 components and building a dedicated factory in Rotherham in order to create the ultra-light Brompton T Line.
The two companies created Brompton Fletcher seven years ago and have previously created titanium components such as forks and rear ends for the Brompton Superlight.
Now at the facility whole frames are precision-engineered in titanium, then orbital and tig-welded for strength. In Brompton’s London home, the T Line is finished with new componentry and tuned for the city, setting a new benchmark for folding bikes in lightness, ride performance and robustness.
Using titanium means that the T Line frame weighs 37% less than the original all-steel equivalent and is just as strong. Weighing 7.45 kg in total, it is comparable to a carbon road bike.
Paul Williams, chief operations officer explained the challenges Brompton overcame to create T Line: “Whilst Titanium ore is a relatively abundant material, turning it into something usable for bike manufacture takes an extraordinary amount of effort. It proves worth it though, as it has the highest strength to density ratio of any metallic element, along with great impact strength and corrosion resistance, making it the perfect material to create the ultimate lightweight folding bike, able to withstand the punishing impacts of the city.
“Working with Titanium takes a high level of knowledge, experience and diligence, so finding the right partner who shared our vision and belief in what could be achieved with Titanium was critical. Our relationship with C W Fletcher, based in Sheffield started over seven years ago and they have a long history in manufacturing going back over 100 years. With them we built Brompton Fletcher, a dedicated company with a purpose-built production facility and skilled team able to work with this demanding material and fabricate these fantastic titanium frames.”
Adam Cox, manufacturing engineer at Brompton Fletcher (pictured, left), said: “All the frames we make are handcrafted and handmade. We take titanium tube, titanium plates, and weld them into frames that then get shipped down to London and built into the T Line bike.
“As a metal, titanium can be quite difficult to work with, whether you’re machining it, rolling it, bending it, or in our case, welding it.”
Matt Kirk, production lead at Brompton Fletcher, added: “It’s not like steel so we have to form it and build it in a different way. We have to play with different wall thicknesses and different bend angles, and with the way we bend stuff, springback.
“It makes you proud that you’ve worked hard to make that weld as good as you possibly can. It’s so rewarding.”