Flat wheels

[Austin 7]

Yes, flat wheels not flat tyres !  Had an advisory on the MOT a few weeks ago that both offside wheels were slightly buckled.  Took advantage of fine weather a few days ago and jacked up the car and span the wheels by hand.  Sure enough, a flat spot on both wheels on the inner rim i.e. the weakest part.  Each probably about 70 mm along the circumference and 3 mm out of round. I can only assume that this was a result of inadvertently hitting a deep pothole or a speed cushion in the dark some time in the last 12 months.

 

Since then I found out that this is quite commonplace and many tyre shops now have a wheel straightening machine.  I took it to one such, and they explained that after removing the tyre the alloy is heated (not too much) and a hydraulic ram pushes a mandrel against the rim in small stages, under the control of a skilled operator.  An hour and £120 later I now have round wheels.  As a further precaution these have been placed on the rear of the car.

 

An interesting side benefit is that the slightly uneven braking (like oval drums if anyone remembers them) I had been getting at speeds below walking pace has now disappeared. I had been puzzled by this, as it felt like there was a high friction or rusty spot on one of the discs, but all 8 faces were perfectly shiny and even.

[Ootohere]

Did the place say that after their close inspection your tyres are perfectly safe after managing to buckle the rims? 

 

What tyres are on the car and what size, and are the XL (reinforced sidewall.) ?

[J.R.]

Let me guess, another vehicle sold new with silly large wheels and skinny rubber band tyres?

[Austin 7]

Just to clarify, these are standard 17 inch factory wheels with 225/50 tyres, no "rubber bands" !

 

No visible problems or unusual wear noted with the tyres, but they were down to about 2.5 mm tread depth, and were replaced a few weeks ago.  The garage that did this (a VAG specialist) balanced the wheels without needing an excessive amount of weight and then carried out the MOT.  That was when the buckles were noted as an advisory.  On querying this, I was told not to worry, that it was commonplace and something they saw all the time.

 

I  was still uneasy, hence my own check and the decision to get them straightened.  The second garage (tyre specialist) told me that the damage was mild compared to some that they have dealt with.

 

The new tyres are Michelin Primacy, and are noticeably quieter than the Dunlops they replaced.

[J.R.]

50 profile is a rubber band to someone of my generation and a 17" wheel huge to someone accustomed to 13" wheels at a maximum, my Minis were all 10" wheels, the Vauxhalls and Fiats usually 12" rims, having a 13" 5.5J rim with 185/60 tyres was the height of sportiness.

 

In all my race cars I never went above 13" rims (by far the greatest choice of compounds back then) never lower nor higher than 60 series profile and it was only the last 24 hour racer that had wider tyres than 185.