Steering Wheel shake (whilst braking)
The usual diagnosis of this at garages time after time is “Warped discs” which is incorrect. If the steering is shaking when you’re braking the feel being transmitted through the wheel is unevenness on the surface of the disc. Now, there could be a fair number of reasons for this. Firstly, the Racing Puma brake setup is a `Track ready’ system with increased thermal capability, this means the bedding in procedure will be different to a standard road car, due to the different temperature characteristics of the pad being used. Brake pads do not transmit material evenly onto the disc until they are up to their normal working temperature (depending on the pad material used of course) and so the with regards to the FRP, they need to be `exercised’ regularly to keep them working efficiently. Correct bedding in procedure is very important with performance braking systems.
Other factors do affect the quality of the braking too like good wheel balancing. The FRP with its firm ride and wide track is very sensitive to incorrect wheel balancing issues and will highlight very clearly to you if they are more than a few grammes out of balance. This vibration causes issue with the quality of the braking system too.
Quality of discs/pads/bedding in/vibration are main causes of this issue but there are also not so obvious factors that also play their part.
Wheel nut torque, many people (and garages) totally neglect this important issue. It is an interesting co-incidence that often the cars I get in that have terrible braking issues and feedback through the wheel are also the cars that I have to almost use a scaffold pole just to undo the wheel nuts.
If the wheel is shaking anyway even without braking, this must be dealt with before spending money on expensive brake rotors and pads!