~70mph vibrations
01-21-2002, 01:09 AM
#1
Burning Brakes
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~70mph vibrations
I remember reading something about this being common on 944's. ANyone have the details? Is this something else other than just maybe unbalanced or flat spotted tires? Thanks.
01-21-2002, 01:17 AM
#2
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On my new-to-me 85.5 944 there was some serious harmonic vibration, but a full wheel balance took care of it--totally smooth up to 90 mph (I need to get more comfortable before I hit 3 figures).
B
B
01-21-2002, 12:07 PM
#4
Burning Brakes
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If you have lock bolts, you might want to have your wheels balanced while on the car.
In that way the weight difference between lock bolts and standard bolts is compensated....
Tace Care
In that way the weight difference between lock bolts and standard bolts is compensated....
Tace Care
01-21-2002, 12:57 PM
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Keep in mind that even if your tires are balanced there may infact be a spot in the tire that reacts differently to the road than the rest of the tire...this will cause a vibration in the car. There are numerous Technical bulletins out on this. There is a new balancer on the market that compensates for tire/rim irregularity. It is called a "load force" balancer. Cars under manufacture warranty should be covered...the rest of us will have to pay (3-4 times the normal charge for standard balancing), unmless you are lucky enough to know someone... 
...I have all the tires for my car done this way.
If you have an open road and good brakes, decent suspension....get into the tripple digits....I was playing with an E46M3 saturday morning 120-130MPH, last week hit 145MPH following a 300ZTT. I have had my n/a car FLAT OUT. in the rev limiter in 4th then until she had no more in 5th. (135-138?)
After experiencing the banks of daytona at 155 MPH on a motorcycle inches from the concrete wall...100+ in a tin can isnt real scary, but everyone has their limits.
Goodluck with the vibration....and I find my car is more stable 80-110MPH (my GTI included)
...I have all the tires for my car done this way.If you have an open road and good brakes, decent suspension....get into the tripple digits....I was playing with an E46M3 saturday morning 120-130MPH, last week hit 145MPH following a 300ZTT. I have had my n/a car FLAT OUT. in the rev limiter in 4th then until she had no more in 5th. (135-138?)
After experiencing the banks of daytona at 155 MPH on a motorcycle inches from the concrete wall...100+ in a tin can isnt real scary, but everyone has their limits.
Goodluck with the vibration....and I find my car is more stable 80-110MPH (my GTI included)
01-21-2002, 01:50 PM
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brh986,
It is fairly comon on the early (pre 1985.5) cars. It is ofter an out of round wheel, unbalanced tyres, or bad tyres. However, it may be compounded by things such as bad wheel bearings, bad tie rod/tie rod ends, bad a-arm ball joints, bad suspension bushings.
Good luck! It is probably your wheels/tyres.
It is fairly comon on the early (pre 1985.5) cars. It is ofter an out of round wheel, unbalanced tyres, or bad tyres. However, it may be compounded by things such as bad wheel bearings, bad tie rod/tie rod ends, bad a-arm ball joints, bad suspension bushings.
Good luck! It is probably your wheels/tyres.
01-21-2002, 02:02 PM
#7
Burning Brakes
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Originally posted by Tabor Kelly:
<STRONG>brh986,
It is fairly comon on the early (pre 1985.5) cars. It is ofter an out of round wheel, unbalanced tyres, or bad tyres. However, it may be compounded by things such as bad wheel bearings, bad tie rod/tie rod ends, bad a-arm ball joints, bad suspension bushings.
Good luck! It is probably your wheels/tyres.</STRONG>
<STRONG>brh986,
It is fairly comon on the early (pre 1985.5) cars. It is ofter an out of round wheel, unbalanced tyres, or bad tyres. However, it may be compounded by things such as bad wheel bearings, bad tie rod/tie rod ends, bad a-arm ball joints, bad suspension bushings.
Good luck! It is probably your wheels/tyres.</STRONG>
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01-21-2002, 02:14 PM
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hey BRH,
ok a few points. I did have the famous 44 shimmy , which yes is common and sometimes uncureable.
Assuming you have a standard set up 44, ie recommnede wheels/tyres/suspensions etc. Also assuming they are all in good coditions.
points to check
1) correct tyre preassure: if a tyre ever got flat spotted get advise from a tyre speaclist.
2) there is a specific way to put the wheel's and the locking wheel nut back on correctly. IT's in the manual, it say's somethuing about making sure the locknut goes on the wheel stud with a red paint tip,check the manual, it does say this can cause imbalances.
3) 4 wheel balance and 3 wheel geometry check.
After I did the latter by the main dealer, this cured my vibration problems , also she handles completely diffferently. Make sure a main dealer does it. IT's a 4 hour job, dont trust it to any garage, who'll tweek it in about 20min,s that won;t do.
hope this helps
ok a few points. I did have the famous 44 shimmy , which yes is common and sometimes uncureable.
Assuming you have a standard set up 44, ie recommnede wheels/tyres/suspensions etc. Also assuming they are all in good coditions.
points to check
1) correct tyre preassure: if a tyre ever got flat spotted get advise from a tyre speaclist.
2) there is a specific way to put the wheel's and the locking wheel nut back on correctly. IT's in the manual, it say's somethuing about making sure the locknut goes on the wheel stud with a red paint tip,check the manual, it does say this can cause imbalances.
3) 4 wheel balance and 3 wheel geometry check.
After I did the latter by the main dealer, this cured my vibration problems , also she handles completely diffferently. Make sure a main dealer does it. IT's a 4 hour job, dont trust it to any garage, who'll tweek it in about 20min,s that won;t do.
hope this helps
01-21-2002, 04:39 PM
#9
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Originally posted by adrian jaye:
<STRONG>
After I did the latter by the main dealer, this cured my vibration problems , also she handles completely diffferently. Make sure a main dealer does it. IT's a 4 hour job, dont trust it to any garage, who'll tweek it in about 20min,s that won;t do.
hope this helps</STRONG>
<STRONG>
After I did the latter by the main dealer, this cured my vibration problems , also she handles completely diffferently. Make sure a main dealer does it. IT's a 4 hour job, dont trust it to any garage, who'll tweek it in about 20min,s that won;t do.
hope this helps</STRONG>
Thanks for the tips but 4 HOURS FOR A WHEEL BALANCE? wtf!?!?
01-21-2002, 04:49 PM
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Apparently the 65mph wheel shimmy also happens on Miatas, go figure.
the front suspension/steering seems to be very sensative to any imbalance, anything from locating the wheel locks correctly to tie rods, ball joints etc.
they all really need to be checked.
the front suspension/steering seems to be very sensative to any imbalance, anything from locating the wheel locks correctly to tie rods, ball joints etc.
they all really need to be checked.
01-22-2002, 07:38 AM
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Renn951, When were you at Daytona and on which bike? I roadrace bikes as well and must agree. After that, anything below 150 feels pretty tame. Maybe I passed you on the outside of turn three? sorry bout the off topic guys
My 944S won't go that fast so I never have to worry right?
I agree with Ren951 that my car actually feels better from 90mph on up. It is a chore to hold it back all the time, like riding a race horse at a walking pace. It don't like to trot.
My 944S won't go that fast so I never have to worry right?
I agree with Ren951 that my car actually feels better from 90mph on up. It is a chore to hold it back all the time, like riding a race horse at a walking pace. It don't like to trot.
08-29-2002, 08:15 AM
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[quote]Originally posted by adrian jaye:
<strong>
2) there is a specific way to put the wheel's and the locking wheel nut back on correctly. IT's in the manual, it say's somethuing about making sure the locknut goes on the wheel stud with a red paint tip,check the manual, it does say this can cause imbalances.
</strong><hr></blockquote>
I can't see any paint on any of the studs. Is it possible to identify the correct stud in any other way?
//Magnus <img src="confused.gif" border="0">
<strong>
2) there is a specific way to put the wheel's and the locking wheel nut back on correctly. IT's in the manual, it say's somethuing about making sure the locknut goes on the wheel stud with a red paint tip,check the manual, it does say this can cause imbalances.
</strong><hr></blockquote>
I can't see any paint on any of the studs. Is it possible to identify the correct stud in any other way?
//Magnus <img src="confused.gif" border="0">
08-29-2002, 10:20 AM
#14
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Magnus,
Just be sure to put your wheel lock on the stud opposite the valve stem on your tire.
Brh,
After changing/checking all of the obvious things(balance, alignment, rim trueness, flat-spots, tire pressure)--the ultimate cure only came about when I changed out the A-arms(my driver's ball joint had completely split). Changed the arms(with Blaszak rebuilts) front end alignment, and all is well
Just be sure to put your wheel lock on the stud opposite the valve stem on your tire.
Brh,
After changing/checking all of the obvious things(balance, alignment, rim trueness, flat-spots, tire pressure)--the ultimate cure only came about when I changed out the A-arms(my driver's ball joint had completely split). Changed the arms(with Blaszak rebuilts) front end alignment, and all is well
