Xantia Alloy Wheel Balance Problem - solved.

[David Goddard]

Ever since my first puncture repair at 20,000 miles, and subsequent replacement of tyres, I have had a slight wheel balance problem. However carefully the wheels have been balanced, there has been a residual vibration - only felt on particularly smooth roads – not many of those in Berkshire! Now 100,000 miles later I have solved it!
At each tyre replacement, the vibration was either more or less than before.
Two weeks ago, I took one of the front wheels off to check the pad thickness. The following day the vibration was noticeably greater. I thought, “Perhaps if I remove the wheel and replace it, rotated by 90 degrees, the vibration may improve”. But how could that help?
Brainwave – how about checking the weight of the regular wheel bolts and the anti theft bolt? The Findings – an anti-theft bolt is 30 grams lighter than a normal bolt!
The Fix – fitted one wheel with 4 anti-theft bolts (that won’t be stolen in a hurry), and used normal bolts elsewhere.
Conclusion – vibration gone!
All very strange, as they are a Citroen part and on the car when I bought it.

[Dave Burns]

You would hardly think that a mere 30 grams lighter on such a small pcd would make much difference but there you go.
You could buy another set of security bolts and put two on each wheel opposit each other, or machine 30 grams from the heads of four bolts and put them opposit the security bolts to maintain balance.
Or get the wheels balanced on the car, then everything that rotates is balanced, including the driveshaft outboard joints.
Dave

[sandancer]

Had the same problem with my Vauxhall Nova with ally wheels some years back when I was a young whipper snapper. One security bolt and severe vibration at 60mph. Put 2 on diagonally opposite as Dave Burns suggests and all OK.
Solution suggested by a bloke from Quikfit. Only thing they've got right in all the years I've dealt with them...

[David Goddard]

Thanks for the suggestions. I agree, 30 grams out so near the centre line shouldn't make much difference. I wonder if new cars have their wheels balanced on the car? Back in the 70's it was quite common and certainly gave a spot on balance.
I have had some real bad experiences getting these wheels balanced. They don't have a hole through the centre so the normal quick mandrel can't be used. Most tyre shops don't have the necessary spider. One simply hammered on a few grams - for apperances sake! Another had a problem running up the bolts on the spider. didn't have the right socket. The wheel must have have been fitted eccentric on the balancer - result about 90 grams on each rim and massive vibration above 40mph! When I complained they said the wheels were out of true. On their machine they were. On the car they were dead on!
I now use a small company in Bracknell, recommended by my Citroen garage. They do a good job.

[Homer]

I've had similar problems with my alloys having no hole in the centre.
One place even suggested I replace the wheels!!
Another took over an hour to replace 2 tyres.