. . . anyone who enters a motorcycle into Bonneville Speed Week needs to get hold of a "Rules and Records" up-to-date book in order to understand and comply with participation regulations. These regulations fall into two part, those affecting the machine and those affecting the riders suitability to participate and protective gear worn.
Here I am illustrating one component of the machine regulations, the 15 degrees rule.
The steering range of the front forks must not exceed a 15 degree turn both left and right and steering must be restricted from turning any further than the specified allowance. This is for safety reasons as excessive turning angles, particularly at speed could contribute to a riders loss of control of his or her motorbike resulting in a crash.
In calculating the margin, we used a measured disc (plastic filler tin lid) with a guidance pin (some straight wire) to measure this out and then cut and welded two restriction brackets onto the front of the frame to ensure a simple and obvious compliance to the regulation. This will make it easy for an event scrutineer to see what has been done to comply with requirements. Simple problems are often best addressed with simple solutions.
A steering damper has also been added to assist in the control and stability of steering.