At around 55mph, it felt like the front tires were "bouncing" up and down.. it was pretty scary when it happened. Slowing down made it go away.

One of the forum members here gave me three useful words of advice: BALANCE THE TIRES

It worked.. Make sure to go somewhere that does high performance stuff (ie. somewhere that has a Hunter 9700 balancer). I went to a place that does work for the local BMW and Porsche clubs.

Never had a problem since.. apparently the W126 chassis is VERY sensitive to improper tire balance.

Neal

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