Technical Bulletin – SC-001
March 29, 2007

Rear wheel nut locking device modification
CAP SAFETY REAR AXLE ASSEMBLY, CR-SC-AH0016B

C&R is making modifications to the rear wheel nut locking device on the Silver Crown car.  This will be a mandatory modification for all USAC teams because C&R is the chosen supplier for this device.  The modification will be made to the plate safety rear CR-SC-0016A and the cap safety rear CR-SC-0017A shown in position 3 and 7 on the diagram below.  C&R require that both of these components are returned to C&R Indianapolis to the attention of Chris Jaynes by Wednesday April 4 for modification.  If parts are returned no later than this date there will be no charge for this modification.  There will be a slight increase in the price of the kit due to the addition of a spring and the cam locking devise.  New parts are pin detent rear safety CR-SC-AH0019A, spring CSA14-67 and circlip MC97633A200.

This new design uses a quarter turn cam lock action to secure the safety cap.  Most teams at the Homestead race weekend requested this change.  Also C&R discovered that under certain circumstances it is possible for the LH wheel nut to un-wind the locking bolt in the original design.  DO NOT remove the two roll pins shown in position 8 below as these are used in the new assembly also.  As a reminder please add extra retention to these pins by dimpling the outside diameter of the axle with a center punch.

If in doubt please contact Bruce Ashmore
Shop: 317-293-4100
Cell: 317-496-9909