spacers cause vibration? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

23109VC · 02-14-2010, 10:19 AM

i'm noticing a vibration in my steering wheel at 75mph or so. at certain speeds it comes, then it seems to go..butm ostly the faster I go.

I hae the maxspeed motorsports spacers on my car - 7mm front `14mm rear. I think I had some vibration before htey went on, but honestly don't remember.

i had my car aligned/balanced 3000 miles ago. that was a year ago.

i could spend an hour or so, remove spacers, then drive...

or leave the spacers on, get it balanced....

just curious if there is any general consensus if wheel spacers tend to cause vibration or if that is rare?

GTA_G20 · 02-14-2010, 10:27 AM

3000 miles in a year? Guess the car's been sitting for some time with such low usage = flat spots in tires = vibration.

spacers will only add vibration if a) poorly designed or b) impropper torque upon installation but Im sure you would've noticed this immediately after your first few road tests. which points me back to flat spotting or your driving over every pothole on the road after only 3,000 miles

23109VC · 02-14-2010, 12:48 PM

i've thought about that, but the mileage is deceiving. The car never sits for more than a week at a time. I sometimes run it to work on Fridays, which means the car only goes 10-20 miles that day, then it sits for a week.... then I'll take it on a longer trip...but normally, it never sits more than 5-7 days before being moved...

If I did get flat spots from extended sitting - wouldn't that go away as the tires warm up, or if the car is driven for a few hours/hundred miles?

i'm wondering if it's more an alignment / balancing issue versus flat spots...

can a tire get a flat spot that is PERMANENT???

blue2000s · 02-14-2010, 01:00 PM

If your wheels are slightly out of balance, spacers can amplify it, as you're putting more of a thrust load on the wheel bearings. Could also be the spacers themselves.

jmatta · 02-14-2010, 04:11 PM

Modern radial tires don't get flat spots unless you've been tracking the car and locked your brakes up heavily; the true definition of "flat spotting".

I would get the car aligned with the spacers and have your wheels checked for balance.

I drive my car less than 3000 miles a year and never have a problem with tires, that doesn't go away as they warm.

BYprodriver · 02-14-2010, 04:29 PM

Most likely cause is the wheel is not centered or to much PSI. Tires do "flatspot" from lack of use especially in cold weather but eventually warm up & the thump goes away.

Boxster44 · 02-14-2010, 05:26 PM

.... agree with prodriver. I had some Fikses for the front for AX and was fine until I used spacers. It seemed sort of a 'hub centric' issue - not perfectly centered.

kj

Lil bastard · 02-14-2010, 08:54 PM

As mentioned, several things can cause or amplify an imbalance. Adding spacers in addition to amplifying can cause vibes of their own.

Agree w/ jmatta - Modern tires do NOT permanently flat-spot - that issue belonged to the era of stell-belted tires where the steel cords had a permanent 'memory'.

The nylon/kevlar cords used in today's tires do not have a permanernt 'memory' and if the tires misshapen due to underinflation, being cool, etc. and hold a shape, as soon as they're inflated and/or heated up, that memory disappears.

The issue not mentioned here is what is the mileage on the tires? Tires can become imbalanced and out-of-round with mileage. Though it's minor and barely noticed, adding spacers will amplify any effects and imho, that's most likely what you're dealing with here.

Cheers!

cvhs18472 · 02-15-2010, 03:00 AM

You can try to re-torque the wheels. Loosen them up, check that the spacers are properly installed and then carefully re-torque. Incorrect torquing of the wheels distorts them and causes a vibration. Cheapest or easiest fix is always the first one to try. Ed

eclou · 02-15-2010, 04:23 AM

while modern tires may not permanently flat spot, they can deform temporarily and cause a vibration. Many tires still use steel belts which you will see if you ever cord a tire at the track.

I get this sometimes on a car that I drive once a week. Usually some driving will eliminate it but you can also over inflate the tire (not to dangerous levels but just beyond car spec) to help quickly resolve it. The tire may have a max of 50 psi and the recommended fill for the car may be about 28-35 psi, so you can bump it to 44 psi or so, run it for 5 minutes then deflate back to normal.

landrovered · 02-15-2010, 05:41 AM

Michelin Synchrone tires are notorious for riding in a lumpy fashion from temporary flatspotting while sitting parked. It was a serious problem at Land Rover dealership when I was the "off road guru" at the local dealership in 2006.

People would come in to test drive the brand new Range Rovers and LR3s and they would ride like crap for the first ten to fifteen minutes until the tires got warmed up.

The key to temporary flat spotting was it did it at all speeds not just at certain speeds until it went away.

I have Synchrones on my RR HSE and they will do it occasionally still but mostly on cold mornings after the truck has been sitting for a few days.

Johnny Danger · 02-15-2010, 02:35 PM

Quote:

Originally Posted by 23109VC

i'm noticing a vibration in my steering wheel at 75mph or so. at certain speeds it comes, then it seems to go..butm ostly the faster I go.

I hae the maxspeed motorsports spacers on my car - 7mm front `14mm rear. I think I had some vibration before htey went on, but honestly don't remember.

i had my car aligned/balanced 3000 miles ago. that was a year ago.

i could spend an hour or so, remove spacers, then drive...

or leave the spacers on, get it balanced....

just curious if there is any general consensus if wheel spacers tend to cause vibration or if that is rare?

Assuming that there are no issues concerning your wheels and tires, I can think of two possible reasons why you might be experiencing a vibration relative to the use of spacers.

1. Correct me if I am wrong, but judging by the photos, that brand of 7 mm spacers
does not appear to be hubcentric. Meaning the design of the spacer does not
incorporate a hubcentric ring. Beyond a 5mm spacer the wheel can no longer make
contact with the "shoulders" of the hub. Therefore, a hubcentric ring with the same
bore specifications must be designed into the spacer in order to replicate the actual
hub itself. Without that, the spacer is more or less "sandwiched" between the wheel
and hub. Therefore, creating a loss of "centricity" between the wheel and the hub.

2. Again, correct me if I am wrong, but I believe that brand of spacers is supplied with
lug bolt that utilizes a different type of ball seat along with a 17 mm head.
If that is the case, and you are using them in conjunction with your oem wheels,
you have created an extremely dangerous situation for yourself.

Flavor 987S · 02-16-2010, 08:09 AM

I hope you are using longer wheel bolts with those 7mm spacers.

23109VC · 02-16-2010, 10:45 AM

the spacers do have a hubcentric ring built into them... at least I think that's what you call it. teh spacer has a little lip/ring along it that the wheel then goes onto... it's not just a flat spacer, it has some kind of ring built into it to guide the wheel onto it...

the bolts are extended, but I do agree they are different. IIRC, my OEM bolts had an extra thing on them, not sure what you call it, but it was like two piece bolt..ther was somethign somewhat loose near the head that probably helped them seat into the wheel perfectly flat. the new extended bolts just look lke bit long cheap bolts.

I found this pic on the H&R site...the spacers I got from maxspeed look simila to these..

[IMG]http://www.************************************************************/images/Porsche/Large/l_P910262.jpg[/IMG]

but teh bolts are more basic looking..

one option is to just try and remove/reinstall/retorque my wheels as-is and see how it works. if the shimmy is still there, then pull the spacers off totally, retorque and see if it goes away.

if I can get the vibration to go away w/out the spacers, that solves my problem..and I didn' thave to pay for rebalancing.

if the problem persists, I can then pursue rebalancing all four wheels.

i have seen quite a few people here who run spacers...so I was sort of hoping to find out if in general - spacers are considered a bad idea, or if they are fine.

i only did them b/c I thought the car looked better with them on, but I'm not opposed to removin them.

i'm not going to upgrade wheels and buy widers wheels..I have OEM turbo twist 18s and I like how they look. my only issue was they dind't fill out the wheel wells quite enouhg...but if spacers are in general - a bad idea and creat problems, i'll pull them off and sell them.

thanks.

Johnny Danger · 02-16-2010, 11:11 AM

Quote:

Originally Posted by 23109VC

the spacers do have a hubcentric ring built into them... at least I think that's what you call it. teh spacer has a little lip/ring along it that the wheel then goes onto... it's not just a flat spacer, it has some kind of ring built into it to guide the wheel onto it...

the bolts are extended, but I do agree they are different. IIRC, my OEM bolts had an extra thing on them, not sure what you call it, but it was like two piece bolt..ther was somethign somewhat loose near the head that probably helped them seat into the wheel perfectly flat. the new extended bolts just look lke bit long cheap bolts.

I found this pic on the H&R site...the spacers I got from maxspeed look simila to these..

[IMG]http://www.************************************************************/images/Porsche/Large/l_P910262.jpg[/IMG]

but teh bolts are more basic looking..

one option is to just try and remove/reinstall/retorque my wheels as-is and see how it works. if the shimmy is still there, then pull the spacers off totally, retorque and see if it goes away.

if I can get the vibration to go away w/out the spacers, that solves my problem..and I didn' thave to pay for rebalancing.

if the problem persists, I can then pursue rebalancing all four wheels.

i have seen quite a few people here who run spacers...so I was sort of hoping to find out if in general - spacers are considered a bad idea, or if they are fine.

i only did them b/c I thought the car looked better with them on, but I'm not opposed to removin them.

i'm not going to upgrade wheels and buy widers wheels..I have OEM turbo twist 18s and I like how they look. my only issue was they dind't fill out the wheel wells quite enouhg...but if spacers are in general - a bad idea and creat problems, i'll pull them off and sell them.

thanks.

The spacers that you are pointing out, are precisely the kind that I was referring to, wherein the design incorporates a "hubcentric ring". However, one involves the use of studs whereby the other simply utilizes longer lug bolts (that's a separate discussion). And, yes, spacers can play a vital role when it comes to certain wheel applications and fitment provided they are design properly and used correctly. Again, I am in the opinion that the spacers that you are using (particularly the front ones) are not suitable for the reasons previously discussed. Furthermore, I believe that you are likely using the wrong type of lug bolt (i.e ball seat and head). Lastly, if you are inclined to have your wheels re-balanced, I strongly suggest having them "road forced" balanced rather than having them simply "dynamically" balanced. I encourage you to do some research on line regarding the benefits of "road force" balancing.

p.s Check your 7 mm spacers again. I don't believe that they incorporate the hubcentric ring.

Adam · 02-16-2010, 12:58 PM

Quote:

Originally Posted by 23109VC

i've thought about that, but the mileage is deceiving. The car never sits for more than a week at a time. I sometimes run it to work on Fridays, which means the car only goes 10-20 miles that day, then it sits for a week.... then I'll take it on a longer trip...but normally, it never sits more than 5-7 days before being moved...

If I did get flat spots from extended sitting - wouldn't that go away as the tires warm up, or if the car is driven for a few hours/hundred miles?

i'm wondering if it's more an alignment / balancing issue versus flat spots...

can a tire get a flat spot that is PERMANENT???

So do you definately get vibration even after say an extended 20+ mile drive? It's not unusual for a tire to flat spot after sitting about a week. Some tires are worse than others. The Kuhmo XS tires I have on my car now flat spot slightly after only sitting a couple days. It can take 10-20 miles or so for them to completely round out especially in colder temps and they've been sitting for awhile.

23109VC · 02-16-2010, 03:58 PM

there is no vibration at lower speeds. it's only at higher speeds.

I took the car out this weekend and drove it about 150 miles. The vibration is there at various speeds. it seems like somewhere around 75-85 it would come on, but also seemed to come/go. it's not like at 75 it starts to vibrate and then woudl get worse and worse the faster I went..

i never notice it below 75. at 75 i feelt he steering wheel shake a little bit..not drasticlly as if I was driving over a washboard...but it was wiggling...as if it was unbalanced.

if I was accelerating, i noticed it less. not sure if that's because the problem is in the front and the weight came off the front wheels..but i'm guessing since i feel it through teh fronts, the problem is up front and when ih hammer it the weight moved ore toward the bck, so I felt it less...but that's what I noticed.

in general, the problem is only there at freeway speeds. i noticed it the most if I was just cruising, at a set speed...

i'll check the front wheels..maybe undo them, retorque them..see how that does.

maybe take the spacers out and try it again.

i distinctly remember when i fist put the spacers on, that I didn't notice any vibation problems... that was several months ago...

i'll experiment with various setups and report back

regardless of what i do, I AM going to look into roadforce balancing.

i went to the hunter website and it lists shops that have the new 9700 machine..or whatever their latest greatest machine is.

it also lists which sites have some special extra feature calld LFM / Straightrack.

is it important to have the car balanced with that LFM feature, or does it just matter to get it done by a place that has the newer 9700 machine??

there is an americas tire very close that has the 9700 but it does NOT hze the LFM feature. the only places near me that have the LFM feature are dealerships that don't do porsche work... chevy, mazda, etc.

will any shpo with a hunter 9700 be able to do "roadforce" balancing? the place that I got my tires balanced at did NOT have this machine, so my wheels did NOT get this type of balancing.

do I need this LFM feature? or is that unnecessary?

Johnny Danger · 02-16-2010, 04:21 PM

I believe that Porsche requires every one of its dealerships to have the Hunter road force balancing system in house. Also, there are a fair amount of independent shops and "tuners" that have their system as well.

p.s. If only you lived closer to the Northeast. I have a few sets of spacers that I would be more than happy to let you try. I am convinced, that at the very least it would improve your situation, if not remedy it altogether.

Lil bastard · 02-17-2010, 01:53 PM

Quote:

Originally Posted by 23109VC

...is it important to have the car balanced with that LFM feature, or does it just matter to get it done by a place that has the newer 9700 machine??

there is an americas tire very close that has the 9700 but it does NOT hze the LFM feature. the only places near me that have the LFM feature are dealerships that don't do porsche work... chevy, mazda, etc.

will any shpo with a hunter 9700 be able to do "roadforce" balancing? the place that I got my tires balanced at did NOT have this machine, so my wheels did NOT get this type of balancing.

do I need this LFM feature? or is that unnecessary?

You probably just answered your own question. If your shop didn't have the Hunter machine - they didn't dynamically balance your tires - it may need to be done again.

The LFM feature is nice but not absolutely necessary; the 97XX system has done a very good job of dynamic balancing tires/wheels for a decade without it.

But, it's not just a case of the equipment, it's also a case of the operator.

To illustrate; I had a 4 wheel alignment done on my wife's Jag when we got new tires for it. I was allowed to be in the shop and observe. The tech spun the tires up, one at a time, on the 9700. This has a graphic readout and as I was watching, he turned off the machine while the graphic on the screen showed the 1st tire off. I commented and he said " The machine gives us a range and it's within that range..." I asked him to spin it up again and get it dead-on-balls which he did, and repeated for all 4 tires.

Next, the car went to the alignment rack. He did the setup and then started the machine. Because it's a Jag, I copied the alignment specs from the Workshop Manual and had them with me. The spec was 0.43. Again the tech adjusted it until it was at 0.47 and started tightening up the trailing arm. I pointed out that the spec was 0.43 and again the tech said the computer gives them a range of 0.39-0.49. I replied "that's just for schmucks who don't know what they're doing... but I bet you can get it right on the dot..." So he loosened the trailing arm and continued to adjust it until it sat squarely at 0.43 and set the other side the same way. I complimented him saying I knew he could do it. Anyway, that car can have a cup of coffee in the holder at 60 mph and it doesn't ripple.

These machines have universal software such as ALLDATA and such which do not always mirror the specs from the factory workshop manuals - remember these are commercial enterprises, it's counter productive to get things down to the Nth degree, they are built on the Move 'em in - Move 'em out principal. In most cases, this is fine, but with alignment and balancing, precision matters. So make sure you know what the correct specs are and have the tech prove to you that he's setting the car to those specs - despite what his database may say.

Cheers!

Mark_T · 02-19-2010, 05:38 AM

When I bought my '99 it had a vibration/shimmy that kicked in at around 70 mph. The problem was that the front tyres were badly cupped, probably from the previous owner running the wrong pressure. Plus he was running different brands of tyres front to back (where do these people come from?). I replaced all four tyres and I get no vibration at all at 125 mph.

Mark