9. Suspension
9.1. Must be fitted with sprung suspension between the wheels and the Chassis and which must be controlled to avoid fouling of wheels on Chassis or bodywork.
9.2. Vehicles of Periods A and B need not have sprung suspension if originally built without it.
10. Brakes 10.1. Must be fitted with brakes that are operative and capable of stopping the Vehicle as required.
10.2. Non-ferrous disc brakes are prohibited unless a Standard Part for that Vehicle or specifically authorised by the ASN for a class or category of Vehicle.
11. Steering
11.1. Must have a steering wheel with a continuously closed rim( except for Drag Race Vehicles).‘ D’ shape wheels are permitted.
11.2. Specifically not permitted are wheels having a noncontinuous rim shape similar to that shown in the Diagram 2( a). Along with other continuously closed rim shapes, those similar to Diagram 2( b)-( c) are permitted.
11.3. Vehicles of Periods A and B may have a tiller or alternative to a steering wheel if it formed part of the original Vehicle.
11.4. Steering movement must be controlled to avoid fouling of wheels on Chassis or bodywork.
11.5. Rear wheel or four-wheel steering is prohibited unless fitted on a Production Vehicle by the manufacturer or permitted under the Specific Technical Regulations or Official Documents.
12. Wheels 12.1. Must have not less than four road wheels and tyres( excluding the spare).
12.2. Must not be fitted with any wheel spacer exceeding 25mm in thickness or of less than hub diameter. Multiple or Laminated Spacers and extended studs are prohibited.
12.3. Must have all hub nave plates and wheel embellishers removed.
13. Tyres Chapter 8 may apply
13.1. Must have tyres complying with Specific Technical Regulations and / or Construction and Use Regulations( if Standard Road Tyres) for the duration of the Event.
13.2. Tyres if treaded must have not less than 1.6mm of tread remaining at the start of a Race except Formula Ford 1600 which must have a minimum of 1mm of tread remaining at the start of a Race.
13.3. Where freedom of choice of tyres is left to the Competitor the responsibility rests with each Competitor to ensure that the tyres to be used are of adequate rating having regard to the potential speed of their Vehicle and the nature of the Event.
13.4. The fitment and / or use of pressure control valves to Wheels and / or tyres is prohibited.
13.5. Unless specifically permitted under the Regulations of the Event the use of chemical tyre softeners is not permitted.
13.6. The interior of the tyre( space between the rim and the internal part of the tyre) must be filled only with air or nitrogen. This does not preclude the use of inner tubes.
14. Cooling
14.1. Must have any fluid carrying lines or tubes carrying coolants through the Driver / Passenger compartment painted red except for HV Battery cooling lines. If lines are non-metallic then must be internally or externally metal braided hydraulic pressure hose. Where braided hose is used then all cooling lines must use anodized unions.
Motorsport UK 2025 National Competition Rules Version 11
Chapter 7 Appendix 2- General Technical Regulations 245