Highway Speed Vibration

My Beck Speedster featured in Reincarnation is all complete with only one matter left on my list - highway speed vibration.  You'd think out of balance but after a half dozen wheel balancing of all types, don't think do.  In fact, we have spun the wheels on the car and they spin out of round.  I've had the wheels checked (EMPI Fuch style) and presumably OK.  I've replaced rotors (EMPI disc) and nothing.  These are lug centric vs hub centric wheels.  Any experience or input?

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Cliff - I think his problem is vibrations he feels in steering wheel and seat of his pants - not the speedo needle.

If " In fact, we have spun the wheels on the car and they spin out of round"  is true then you'll never get  smooth ride with egg shaped wheels.  You can have tires pulled off and they can spin the rims alone on the balancer to see if they are out of round.  You might find 2 are better than the other and use those for the front.  Like Calmotion said may be okay for back - or for a garage decoration.  At price I assume the EMPI Fuchs aren't scrutinized by German Fuchs TUV standards - just round enough.

You mentioned lug centric.  Are you using the right lug nuts?  There are round ball shouldered and tapered acorn bolts/nuts.  Are you using bolts or studs with nuts.  I've been looking at the CIP1 Fuchs with 5" backspacing http://www2.cip1.com/ProductDe...=ACC-C10-6649 - and in one place it says "These wheels are machined to use tapered 60 degree acorn style mounting nuts or bolts." But if you click on wheel hardware for that wheel it says "C32-6655 - CHROME PLATED 14MM WHEEL BOLTS WITH BALL-SEAT - WITH 1-1/4 INCH THREAD - 4 PIECE SET" http://www2.cip1.com/ProductDe...ProductCode=C32-6655

If you have the wrong nuts/bolts then they aren't making much contact with wheel and could be moving around.  Maybe pull a wheel off and put some paint on the seating part - and see if it makes full contact with the wheel.  Might be obvious - but as you put a wheel on do so in a cross diagonal pattern (not around the wheel).  This will seat wheel properly as you apply the right amount of torque with a reliable torque wrench.  I avoid torquing wheels at places that use a rattle air gun - even with the supposed torque extensions.  Old fashion beam torque wrench for me.

Image result for acorn vs tapered lug nuts

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I've been looking for one of those for years.  The one I used to use at a local gas station way back when was a Hunter.  Big, saucer-shaped thing that clamped into the rim from the outside, and it had 4 or 5 or 6 little wheels on a shaft that stuck straight outward from the center.  You get the wheel spinning (I usually just used one of the rear positions and spun it with the engine) and as it was spinning you twiddled those little wheels on the shaft  and you could feel it getting smoother and smoother until it was vibration free.  Took maybe a minute if you were good.  

Then, you stopped the wheel, read the weight numbers in the windows of the saucer-balancer-thingie and added the weight it said at the arrows it indicated to the rim.  Tap (or glue) them on and move to the next wheel.  I could do all four in less than an hour including moving them around.  

When I had my first Dune Buggy, the rear rims were two stock VW rims on each side, welded together side-by-side at the inner rim - kind of like a poor man's Dualie buggy.  I did that to fit a single 285X16 tire on each side.  The ONLY way I could balance those was while they were on the car.

So, Mr. Grey, either find one of those somewhere local (trust me, there aren't many around, these days) or try getting them road-force balanced or live with it, but I would start by having someone first check the rims for wobble-trueness and roundness and then go with a new (and different manufacturer) set of tires.  I started out with a set of Continentals that each took, on average, (18)  1/4 oz weights per wheel!   Put up with that for a long time and finally went with a set of Michelins which took maybe 2 or 3 weights each.  Still had a very slight tremor at 65, but WAY less than the earlier tires.

I just went through the process

first check rim or wobble for out of round 

second, check tire I had one in back that the tread was moving left to right ... changed it

roadforce balanced them 

they moved the tire to compensate for issues BMW allows 5 lbs I think out some wheels are horrendous my fuchs were 8  

Solved issue ehat a difference in ride 

my P rack and pinion still has a bit of play in the joint of the steering but they all do somewhat

 

Find where you are out of round, shaving tire is not the answer but a Band Aid fix. You'll  need to start at the axle / spindle checking the run out with a micrometer, then mount the rim checking that it is secure ( correct lug nut to rim) and flush on the car then check the rim run out.  Tires can be out of round and any good tire guy will first try popping the tire beads and rotating the tire 1/3 on the rim re-inflate and check run out before balancing. Might have to do this at a couple of positions . If the tires are still out of rounds, replace them

Hello everyone, first of all, i have to say, what a great forum!

and sorry for my bad english but I try hard.

Beside al the tings already mentioned there is one big thing that can also cause your problem. Is your steering gear well adjusted?

Background: if the steering wheel is absolutly straight it should be possible to turn the steering wheel around one inch to the left and right without any response on the wheels. When you drive straight ahead, the wheels can shake a bit without any response in the steering wheel. If your steering gear is adjusted too tight this will not happen and you feel every movement in the steering.

For this, there are two things to check. There is a mark on the steering gear. if your steering wheel is in "0" and the car is driving absolutly straight ahead, the mark on the steering gear should be in the right position. 2nd in this position you should be able to turn the steering wheel freely one inch to left and right without any resistance.

If this is the case, you dont get these little movements in the steering wheel anymore cause the steering damper can take over.

If its not the case:

How to adjust the steering gear you will find in al the service manuals of the beetle.

Best wishes from Germany

 

Jan

Alan has it right.  A competent alignment shop will always start with the simplest fixes: tire integrity, balance and correct air pressure, then move on to wheel alignment (including out-of-round), front end adjustments, and axle/hub run out.  Other car guys/clubs in your area will usually have a favorite alignment shop.

I also feel that hub centric hubs hold the rim in place where other hubs will move around somewhat on install as you tighten the nuts and may cause some hop 

i know also yhat some original Fuchs has holes that were not in the center and my P mechanic says one guy went so far as to have his rims machined true then went and created center cones for his hubs to hold the wheel aka hub centric 

 

Without the steering damper a worm and roller VW or P356 steering box gets the shakes like crazy, I have lived it and the symptoms are like this... you hit a bump even at 30 mph and the steering wheel shakes maddly ... ... No such animal in a Rack and Pinion. 

Alles ist gut. It was directed to Agate Grey - know he has a roller Beck.  Beck welds the VW front beam to the tube chassis - they also use a std vw steering box which would accommodate the steering damper.  Just wondering if perhaps it was left off.

I bought a rotor from cal imports and it was not concentric. If yours are not concentric and you have hard shocks you will get vibration at freeway speeds.

Vibrations come from imbalance not from a bad or not installed dampener. Granted, a dampener is a must on a bad road so you have to be able to differentiate between the two.

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