The Failed Wheel
The wheel that failed on the pothole was a BBS wheel made in Germany.
Here are some pictures.
Grr! Potholes
Last night, I had to go into Newmarket to get some shopping.
Unfortunately, I hit a very deep pothole in the dark and it completely ripped the tyre off the wheel of the Jaguar. Now, you could say that this was because the tyres were worn and dangerous! But the car had its MOT on Monday and as it needed a new tyre soon, I got them all checked and ATS in Newmarket fitted two new tyres that day. So the tyres were tip-top.
I’d not put a jacket in the car and as I was late because of the puncture, I didn’t change the wheel last night. So I just left the car a about a hundred metres from where the damage happened on the Dullingham Road into Newmarket and then I had the expense of a taxi to get home. I then realised why I don’t use taxis in Newmarket. They are very expensive.
So now, I’m going to take the Lotus and go and replace the wheel on the Jaguar, before driving that to the repairers. Hopefully, I’ll be able to get the Jaguar back later in the day with a new boot.
I’m also going to try to find the pothole and take some pictures.
These pictures are the ones I took when I returned on the Saturday morning.
Pothole 1 - Newmarket-Dullingham Road
This was the first possible culprit I found and it is almost 10 cm. deep.
Pothole 2 - Newmarket-Dullingham Road
This one was equally deep, but I suspect too narrow for the wide tyres on the Jaguar.
Potholes 3 and 4 - Newmarket-Dullingham Road
I think one of these two caused the puncture. Note how the road has broken away from where it was repaired. As someone was going the other way at the time, it would have been impossible to avoid going into the holes. Again the holes were about 10 cm. deep.
At least when I got to the car it was still where I parked it in a quiet street.
A Puncture
It didn’t look too bad.
In fact, when I got the wheel off and replaced it with the usual silly drive-home spare, it looked almost intact. Which I thought was good as I’d driven the car perhaps a hundred metres from the dark, where the puncture happened to the lighted street on the edge of Newmarket.
It was only when I looked at the wheel fully, that I realised what had happened.
Jaguar Alloy Wheel Failure
Note the perfect crack all of the way round.
One thing that has to be said though, is that the tyre held everything together and it did not appear that any other damage was done to the car. I think I was lucky.
So why did the wheel fail?
I was not travelling that fast and was probably doing about 50 mph or so, as it was dark, wet and I was in no particular hurry. I think that sort of catastrophic failure at a higher speed would probably have meant the disintegration of the tyre. In any case, the car was very controllable and I was able to slow it down very easily. This again would probably be impossible at a high speed, as the imbalance in the wheel would probably have caused everything to go very wobbly. There was no vibration at all.
I just wonder if it was one of those occurrences where the frequency induced by hitting the pothole was exactly that of the wheel and that caused the splitting of the rim. I might have hit both potholes 3 and 4 and this double blow could have caused it. But I only heard one loud bang, which I now presume was the wheel splitting.
I have worked in this field of whirling shafts and weights, and there are some very strange phenomena, when you compute everything properly.
When I changed the wheel, I took the car to ATS and the mechanic there said he’d never seen a wheel split like that. Especially, after they had checked all the wheels and tyres earlier in the week.
I have sinced searched the Internet for anything similar and have found this report by David Finlay. The car in question in his report was a new high-performance diesel Mondeo, with the same engine to the X-Type.
As my Jaguar was made by Ford, are the wheels made by the same company? They look fairly similar.
The Anonymous Widower 