Steering Judder

[johnthebass]

I recently replaced the front tyres (215/50/15's) on my Excel with the wheels firstly being balanced and then re-balanced with the tyres fitted much to the puzzlement of the tyre depot who fitted them! Whilst there is no "wheel wobble" I am experiencing some steering "judder" upwards of 85mph ( ooohh I hear some speed limit fanatic say!). The car was last week at Chris Foulds Motors for an "A" service and I specifically had him check the integrity of the front suspension and steering rack for wear etc and no problems were found. Has any other member experienced this and if so did they find a cure?

[Simpatico]

Mine was partly down to a slack front bearing.

[robertverhey]

Mine was eventually fixed by skimming the discs.

[Lotus-e-Clan]

Balancing can easily be cocked up if the fitter doesn't follow the rules as per Excel WSM. IIRC it's important to use the correct cones in the orientation recommended.

Initially my wheels were balanced correctly as far as the fitter was concerned but on the road I got vibration at high speeds so I insisted that he used the Lotus WSM procedure (which he'd never heard of and was miffed that some one else knew stuff he didn't about wheels and tyres )

Result..no vibration all the way to 140 mph!

[johnthebass]

Peter K refers to the "Lotus WSM procedure" exactly what is this? Roberts suggestion as to skimmimg the discs seems to me could be worth while trying as there is some wear.
Thanks guys!
John The Bass
Excel SE
Eunos Roadster
Honda Aerodeck

[robertverhey]

The service notes (I assume that's what's being referred to) are quite specific about how wheels should be attached to the balancing machine, with use of specific cones, front and rear. It also specifies the tolerances. Can scan and provide if you wish. My experience with tyre fitters is they don't like being told their job, and they just want to get 'em on and get 'em off the balance machine. So hope you can find a someone who's prepared to do it "by the book" like Peter did.

You may find the problem in the wheel balance, or the disc skimming, worn pads, sticking caliper, or the suspension geometry or in steering rack play, ball joints, upper ball joint, wheels or tyres out of true, wheel bearings...... There's any number of reasons. It's just a matter of checking one thing at a time until you find the problem(s). As Cap'n Bob told me soon after I'd bought my Excel, and when I had a million questions, Excels are designed to very close tolerances, and everything needs to be "right". But if they are right then the car will be solid as a rock right up to max speed. As for mine it's still a work in progress 5 years down the track.

[johnthebass]

Thanks Robert! Of course WSM ie Workshop Manual!