Wheel balancing, or is there a different cause? Options

[JohnB]

I've owned three 914's over the last 25 years and all have had the same issue. At some speed between 60 and 70 mph I get the kind of shake you'd get from an unbalanced wheel. Even after having the wheels balanced I always get it and I've had every kind of wheel and tire combination (steel and alloy wheels of every kind, Yoko's, Bridgestones, Michelins, and Vredestein tires, you name it.) I've talked to a few other owners and they report a similar thing.

Is it possible there's an unbalanced half shaft causing the problem or some other thing like an out of round wheel I haven't discovered? Why can't I get the tires to act balanced?

The easy fix so far is to either drive lots faster (IMG:style_emoticons/default/driving.gif) or lots slower (IMG:style_emoticons/default/dry.gif) but I'd rather not have the problem.

I've also had the alignment checked and at least on my current car all's well except the right wheel camber (or maybe they said caster). They can't get it into spec. The shock mount looks like it's all the way forward and maybe that's part of that problem.

ideas?

[Spoke]

I have the same problem of unbalanced wheels even after having the wheels balanced. On my 71 I found the issue to be the lack of a centering ring on the hubs. The wheel could be tightened down in any number of positions that are not exactly in the direct center of the hub.

I ended up getting a pointer (basically a pencil in a portable vice) and for each wheel, spinning the wheel to see if the wheel is centered on the hub. If not centered, loosen the lugs, re-center and repeat until perfectly centered.

The wheels that I refer to which are so difficult to get perfectly centered on my 71, give me no problems on my 74 with front hubs with centering rings.

Spoke