6UL wheels were concived and designed for competition use, while they are perfectly at home on the road, they are optimised for competition.
Fitment. This is designed for four M12 studs and nuts or bolts on 100mm PCD (4x100). The the mounting seat is a standard 60 degree cone.
Spigot (centre) rings are no longer supplied and are not required. The close fitment of the studs ensures the wheel is all but central and the locating action of the wheel nuts / bolts locates the wheel central on the hub.
Overall wheel weight is reduced by being optimised for 4x100 fitting. To provide for other sizes, additional metal in the hub area, resulting in additional weight, would be required and the light weight properties of 6UL would be lost. Weight is all important in racing, slowing extra weight down for a corner and speeding it up again afterwards all takes extra effort as well as the vital suspension control. Paint on the interior of 6UL wheels is deliberately kept thin, it all adds to that extra weight.
- Inspect your wheels before you mount tyres for the first time. A scratched wheel with a tyre on it is not warranteeable.
- Torque lugs to 70~80 ft-lbs ( 94Nm~108Nm)
- After first drive on brand new 6UL's, retorque once.
- Retorque nuts after every track session or autocross day.
- Wash with mild soap and water. Strong degreasers will stain the finish.
- In common with all alloy wheels, winter road salt can damage the finish and cause corosion, wash your wheels reqularly.
- Check track wheels for roundness and cracks every time you replace the tyres. Track wheels get bent, it's a fact of life, we see hundreds of them at MOT, literally :)
- New radial runout spec is .025" lateral runout spec .015. Replace at .090 radial, .060 lateral 6UL's can be static balanced for track use. The 9" might require dynamic balance due to the width.