Hi Nick,
Your worries pale into significance when you here my story!
In my S1 yeaterday when I was buzzing along the road between Burford and Stow at a steady 50 mph when all of a sudden there was a bit of a "lurch" to the LHS and I was overtaken by my rear wheel !!! By luck/fate I managed to "glide" into a layby about 300m along the road. Getting out to first of all stop the shaking in my legs, I looked at the rear wing and luckily it was only slightly buckled and the stub axle saved from serious damage due to the rear disc and the new side exit silencer taking all the weight. The wheel was in a ditch over 100m in front of me but the issue was -where was the nut (other than the one driving the car!) So, I walked back along the road and luckily found it in a ditch half a mile away !!
The RAC sent a recovery truckand we managed to jack the car up with an assortment of wooden blocks and the wheel went on and the thread was ok!The grub screw was still in the nut and was about 6mm through onto the axle slot. It had new tyres recently and I witnessed them tightening the nut up and tightening the grub screw.
Now the real puzzle - the same thing happened a year ago and on the same corner - that time it was a new stub axle. So, what is happening? I did notice on the nut, that the "mating" surface was very small - judging by the amount of scoring on the surface. Could this be the issue ie the nut is just not gripping the wheel sufficiently??
Sorry for the long ramble but I am seriously thinking about "moving on" as it really could have been a very serious accident
T
Nick - just check your nuts!!
If the wheels and wheel nuts are not put back on the same axle stubs that they were removed from, IE NSR wheel goes back on NSR hub etc, then the grub screws will not line up with the slot cut in the stub axle.
The slots were cut into the stub axles as a dealer recall after several cars lost wheels.
And it was done by the simple expedient of tightening up the replacement wheel nuts, marking through the grub screw hole with a pen, then removing everything and filing a slot onto the stub axle.
Manufacturing tolerances being what they are, it is very unlikely that one nut will fit onto another stub axle and the grub screw will line up.
Incidentally, on the GT Cup Aero we just tightened the wheels up to 380 lbs/ft and never had one fall off
Simon@Sifab.co.uk
