rmac Design...

Since development work started in 1998, every Armac Design product has been designed, developed and tested by Duncan and his test team. Every product exits for a specific reason, and every product works to benefit you and your bike. Our aim is to increase performance, which ultimately means more enjoyment and a better ride.


Duncan built his first motorbike – a monocoque Ossa – at the age of 18. (See newspaper clippings below from ‘Motor Cycle’ newspaper 1974, and Motorcycle Sport June 1974, featuring Duncan and his home-made Ossa, which he rode in the Scottish Six-Days Trial). He genuinely has been leading the way in frame building innovation, for nearly 40 years!

After competing in, and building parts for, grasstrack, speedway, enduro and trials, he took over his father’s Triumph Tiger Cub. In 1998 he decided to improve it...

With encouragement and input from Dave Thorpe, Duncan built jigs, researched componentry, and built a main frame, swinging arm and rear sub frame. After a year’s testing of two prototypes - one under Dave Thorpe and one ridden by Duncan - the first production, of 10 frames, was made.

More than 15 years later, Armac Design is known and respected for building top quality, lightweight, highly competitive frames and components.


Any questions, please get in touch: [email protected], tel 01751 417371


Telephone: 01751 417371

Address: Holme Cottage, Appleton le Moors, York YO62 6TE

Email:  [email protected]



Invoices will be issued by R.E.H Forks Ltd. Please add VAT at 20% to published prices.

Payment is by cheque or bank transfer

Paypal is also possible but a commercial fee is charged.

...is a family business, run by engineer Duncan Macdonald and his wife Judy. They are proud to make unique, original products in Britain, backed up by personal, friendly service.


Logo VTC-1 JA-reliance VTC-2012-4 cub3 JDF-1 JDF-2

Duncan in action on his Armac Cub at the Ventoux Classic Trial in France; Judy enjoying her Cublet at the Reliance round of the NBBC (picture: John Hulme/Yoomee Products); Duncan at the VTC; and in action in Rosedale, Yorkshire: home ground.

Below: ‘Motor Cycle’ newspaper 1974, and Motorcycle Sport June 1974, featuring Duncan and his home-made Ossa.(Front page of Motor Cycle that issue was ‘Mick Grant signs for Kawasaki’...)