Several owners of the bike have reported a creaking sound coming from the fork, and the company says that there have been two instances of the steerer becoming detached.
A statement from the Yorkshire firm said: "We have become aware that a number of 2014 Orange RX9 bikes were made with forks that have a potential risk of breaking. Under certain circumstances, the fork steerer tube can become disconnected from the rest of the fork."
The company's webite offers more details.
The issue relates to the height of the fork cathead, which connects the fork steerer tube to the legs of the fork. Affected forks have an undersized cathead, which means the join is not strong enough.
Owners of an RX9 can check their fork to see if they need to replace it by measuring the depth of the cathead. The faulty catheads are 30mm at the centre across the cathead. Forks that are safe to use are 35mm at the centre across the cathead.
The faulty fork's cathead is only 30mm long rather than 35mm
If you own a faulty fork, Orange advises you to not ride the bike and to contact its warranty department by emailing email@example.com to request a replacement, which Orange will provide at no cost. The replacement forks will be available from 7 November, 2014.