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perhaps it's just me ...but this seems odd that my original set of tires wore out so quickly....they were cirello "blacklion " 195/65R15   knowing mr JPS he probably did not use lets say high $$$ michelins as OEM on his cars...which is just business which  i can understand....i took photos of the tires...these are 4 years old and only 13K miles...had no idea when i took them off to do some maintenance the fronts were this badly worn...pretty unnerving after knowing how much wheel i was putting into a a few curves lately...luckily this car doesn't see wet roads as a rule...i replaced all 4 with a same size better bridgestone model tire,,,,both fronts and rears were worn in more or less the same pattern...and alignment was not an issue i was told by my tire guy .... i don't think so either since this car tracks down the road just fine...is it20221126_08520220221126_090202 just the nature of these cars on a lowered front beam since there is not many adjustments that can be done?...and the rear IRS transaxle is what it is concerning tire stance i believe...any thoughts from the genius replica car gurus?....thanx for the expert opinions in advance  ...in the photos the more bald tire on the left is the right front with the extreme wear on the inside of both tires  and the rears in the photo is left tire is the right rear again with the more obvious wear on the inside of the tire

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That is caused by too much negative camber (tires leaning in at the top). With lowered front spindles the stock camber eccentrics don't have enough adjustment for zero camber. I had this problem but mine had too much positive camber so tires wore more on outside. Like yours my car drove straight because the toe was set correctly. These solved my problem.  VW Camber Adjusters | 22-2817 | JBugs . I don't think there is anything you can do about the back.

As @sethsaccocio said, you need front adjusters with more range.

The rear is more complicated. The springplate to diagonal arm relationship can be adjusted to gain a small measure of positive toe.  If your car is significantly lowered, there is not nearly enough adjustment to correct for this.  
Depending on how much work you want to do, there is a fix for this.  The diagonal arm has about 1 to 1.5 degrees of negative camber built in.  You can flip the diagonal arms over from one side to the other, but to do this you have to cut off the shock mount, and reweld on the other side.  This is not something for the someone without some fabrication experience. Most just learn to live with the tire wear.

If I was doing this, I would do exactly like I did on my 1958 Ghia.  I’d narrow the control arms, and take the camber out when I weld the bearing housing back in. Kills 2 birds with 1 stone.

I had the same problem on my rear tires.... even after replacing them they were bare again after 3000km! It turns out it was not caused by incorrect camber, but by toe-out. Too slight to see by eye, but i found a garage with a toe-out/toe-in testing floor. I asked nicely, and they let me drive it slowly forward onto the testing floor myself - to find that my rear tires had 3 times the normal amount of toe-out (so the front of the tires were pointing out rather than straight forward).

I didn't think it was something I could fix myself, so let a local mechanic have a go - but he was equally unsure about how easy it would be. Turns out it was a 10 minute job! Raise it on lifts, and there were only a couple of easily-adjustable .... shims?.... bolts? on the rear swing arms. Not an exact adjustment, but he got it right first time and after retesting it on the other garage's measuring floor it was perfect.

So my advice would be to find a local garage with the floor tester machine, for a quick diagnosis.

That major asymmetric wear is a toe in (or out() problem. One needs a slight toe in at front for stability.  My JPS had a crazy amount of positive (toe out) set when delivered.  As in, nobody ever looked at it, I'm pretty sure.  One can set the toe by just using a tape measure and a nice stick.  You raise the car, hold a pen ot other marker to the tire , rotate the tire to draw a circle on the tread.  Lower the car and roll it forward a a rotation or so, measure the distances of front and back of the circle you drew. Front of tires need to be slightly closer together than the back of the tire, maybe 1/4 inch?? That is: toed in. Tie rods are built to be adjustable for this purpose.  Not a really bad shade tree mechanic job, actually.  Of course just about any garage or tire store can handle such a thing with special measuring devices.   As to the rear, you have posts here that indicate that job is a little different. I've never seen a car with crazy bad toe in the back, but I guess it can happen.

Front toe in should be 1/8 to 3/16 of an inch. Obviously, a real alignment at a real shop is your best option.

If you can turn the tie rod ends and put the car on ramps the toe can be set from underneath with two flat sticks that overlap in the middle. I use two lengths of angle aluminum nested together to make them easier to handle. Measure at the rim, is best, but you have to remember to extrapolate out to the edge of the tire at its horizontal midpoint.

You could also use the sidewall transition groove on the tires, if they're new. That brings you out close to the edge and a little more than a 16th to 1/8th there is going to be pretty close.

@DannyP  haa!..guilty as charged concerning the shows...tooo bad i can't sell my trophys to pay for mechanics...haa!....and i believe i'll take you up on your advise 100% since you have forgotten more about these cars than i will ever know and save my $$dough$$ and hire a pro to replace the aftermarket camber parts/ ball joints and do a proper alignment while the tires are brand new...way above my pay grade...FYI i do grease my beam every oil change ....but lack the alignment shop in my garage...again thanx to the group for their input

@jncspyder

For the rear toe-in, sometimes the slots in the trailing arm aren't long enough and you can't get any toe-in or toe-out or even get the rear end to zero. A bit of time with a small bit in a die grinder is what they need...

As for specs this is what I use:

1/16" toe-in in the rear(IRS can be pretty much zero), a slight amount of negative camber in the rear: 1 degree or less. ALWAYS set the rear up first, and get them equal as far as toe-in, other wise the car can dog-track. We certainly don't want that!(Swing cars get more, like 3 to 3.5 degrees negative. Stops or straps to prevent going more than 1 degree positive at droop are recommended as well. I have such straps.)

I also set the front up with 1/16" toe-in. Some guys use 1/8" but if everything is in good condition the smaller amount works fine. I use 1.5 degrees negative camber in the front, but I corner pretty quick. Negative 0.5 degrees is fine for a cruiser. An added benefit of the aftermarket camber eccentrics: If you go mild on the camber, you'll end up with a couple degrees of extra caster(which you'll need with a slammed front end). Just tell the alignment guy to make sure the eccentric leans the spindle BACK instead of FORWARD(VERY IMPORTANT).

If the shop has scales and you can corner-balance it, DO IT! A properly balanced and aligned car handles like NOTHING else. It is a difference that needs to be driven to be known. In fact, you won't be able to put your finger on WHY it feels so right. It just will.

Sometimes people leave the steering stabilizer off. Don't. And use a front sway bar if swing axle. If IRS, use a front AND a rear sway bar.

Cheers.

Last edited by DannyP

tire wear update....had my car properly aligned today by a proper pro alignment mechanic in camarillo...seems my problem was a very poor attempt at the initial alignment when the car was 1st delivered from john boy....and it seems there was enough adjustment so as not to need the aftermarket camber adjusters....luckily unopened packages can be returned to JBUGS...photo included to show now correct specs....rear was advised to leave as is...time will tell with future tire wear...another installment of "SAVE YOUR $DOUGH$ ,and HIRE A PRO" .....thanx again to the group for their insight and advice 20221207_155927

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Your caster is too low.  LF is 2.3 degrees, should be minimum 3, for higher speeds closer to 5 is desirable. RF is .5 degrees, that is very low.  This will cause handling issues at speed.  Did your alignment guy mention this to you?
The yellow box means marginally out of spec, the red box means way out. Green means good.

@LI-Rick posted:

Your caster is too low.  LF is 2.3 degrees, should be minimum 3, for higher speeds closer to 5 is desirable. RF is .5 degrees, that is very low.  This will cause handling issues at speed.  Did your alignment guy mention this to you?
The yellow box means marginally out of spec, the red box means way out. Green means good.

^ that

@jncspyder - I've got 8-1/2 deg of caster, but i'm a gorilla - you might not like wheeling that through a parking lot - but I'd still want to see at least 5 deg of caster. If you aren't corner-carving, 3 deg of camber in the rear is plenty. More will really accelerate wear on the inside of your tires.

I was assuming the pictures you showed (of the very uneven tire wear) were of the rear tires. Was that not correct?

@LI-Rick now that you ask...he did ask me if i drive fast....i told him i don't push this car hard...and i don't...this car is not a GT3...i was more concerned about wearing out front tires in only 13K miles....it felt fine on the way home....if i feel uncomfortable with the handling, i'm sure he can make the needed adjusting....he's a really good guy...very knowledgeable and said it is way better than before

@Stan Galat  no stan...the rears wore somewhat evenly...it was the fronts that were badly worn....those photos were taken after removal from wheels and not properly oriented ....tire in left of the photo was the right front & vice versa ....both R & L front tires were badly worn on the inside after only 13K miles!!...not good!

Apparently, there are no aftermarket caster shims installed in front.  Buy a set of 2 - pairs and a set of 2 longer mounting bolts and have your alignment guy add one (or 2) either side.

About $15 per pair and $10 for the longer bolts (required if 2 shims per side are needed).  Any online VW shop or Amazon/eBay has them. They go behind the lower H-beam axel piece.

Image result for VW Caster Shims. Size: 176 x 185. Source: www.megabug.co.uk

Last edited by WOLFGANG

@jncspyder- As mentioned, the extreme tire wear you were experiencing had nothing to do with the tires themselves- the camber settings were the culprit. Expensive tires will wear the same way with that much camber, and at the same rate.  With the less radical front camber you'll find the front tires now will last way longer.  What's concerning us is the lack of caster in the front- with those numbers I'm guessing that at highway speeds the front is 'a little twitchy' (it gets tiring on long drives- I know this because I've been there!) and the car gets more uncontrollable (and dangerous) the faster you go. I also know this from experience- when I was a much younger man, knowing nothing about caster (and what the lack of it does) I bracket raced my Cal Look Beetle (with the front end lowered via cutting/welding the beam) a few times a year and at the top end of the 1/4 mile track (88-89 mph through the lights) it was always a handful keeping it in my lane. At over 100 mph (coming back from Whistler down a long hill) the car was frighteningly scary to drive- a side gust put me in the opposing lane before I could react! I only took it up that high once, and I'm thankful to this day there were no cars coming the other way.  I discovered these magical things called caster shims shortly after.

The (front) caster readings suggest your car doesn't have offset spindles and was lowered by modifying the beam- either by cutting 1 or both center collars, rotating slightly (usually 1/8 or 1/4") and rewelding, or replacing said center sections with adjustable units.  Caster shims behind the bottom beam (@WOLFGANG showed a pic of a pair) will give your car back the much needed caster and make it safer to drive.

I just noticed- the discrepancy in the left/right front caster #'s is a little surprising, and suggests maybe a bent beam/frame head or tweaked trailing arm (remember, most Beetles did become donor/parts cars because of collision damage).  Most aftermarket shims today are 5-6 mm thick and add 2- 2½ degrees caster, so 2 shims on the low side and 1 on the other will get you in the neighborhood of 5°, which is the same number as all 356's (and we all know how well and predictably they handle at higher speeds).  This will make your car a rock solid performer at highway speeds (and above).  And I know, even if you don't normally play at those speeds, all it takes is a moment at above the posted speed for something to go wrong- better to be prepared.

Some reading about caster- http://www.geneberg.com/cat.php?cPath=12_384_2917

Hope this helps.  Yoda out (time to go back to bed it is!)

Last edited by ALB

It appears to me that your alignment guy didn't touch the rear alignment at all. Your new rear tires are going to wear just like the old ones did, and in the same time frame. If you have an IRS rear, that much negative camber is unnecessary and tire-wearing.

As I've said before, adjust rear camber, then toe FIRST and set the proper thrust angle. Then and only then move on to the front.

You definitely want MORE caster in front than you have. Doesn't matter if you cruise or thrash the car. The shim hints are great.

I realize I'm the only one who says this(and nobody listens), but the aftermarket camber adjusters will give you MORE caster if you don't use them to give you extra camber. Think about it, it works, and will tilt the spindles back a degree or two and give you extra caster.

Or do the shims, and I totally agree with Al and Rick. Put two on one side and one on the other and it will even out the caster side-to-side.

The figures the alignment guy gave you are puzzling. Your rear camber was (still is) a bit much, your front was close to right (0 is spec, though .3-.5 degree negative is what I set mine at), and yet the front tires wore crazy?

It's exactly the opposite of what I would expect to see.

Also ditto DannyP's comment. He actually knows how to align a car properly because he taught himself and then bought the stuff he needed and did the job—several times at least. Most of us here (myself included) are more or less knowledgeable amateurs. Piperato is much more professional.

@edsnova todays update...drove up the coast about 40 miles....usual speed the car likes on the freeway around 80mph-ish...the car seems just fine as it was before.... tracks straight brakes straight...feels very tight...all seems good...the way i drive this car with relatively "kid gloves" and not a crazed canyon carver i think it is just fine....i talked to a vw guru guy in simi i know and he also agrees with the shim thing as a possible way to go and he said drive it and if it seems fine and not showing any wild characteristics it should be ok... i agree about listening to @DannyP...he's the man...he's forgotten more than i will ever know about these cars, so i will investigate the "SHIMS" saga further.... thanx for the group chat with the  gurus as always!

"Drive it and if it seems fine and not showing any wild characteristics it should be ok."

I agree with your wrench - If it feels fine at your usual driving speeds then just drive it!

I would just caution you that it might exhibit "bump steer" but only when you're moving near a stoplight where the lanes have crowned in the center due to truck traffic and it'll want to play around with the peaks in the lane - Nothing to really worry about, just be aware that it might sway back and forth to follow the peaks.  It's doing that just to see if you're awake behind the wheel......    😉

I find it disturbing that the tech knows what the specs should be and did so little to make it correct.  I spent a couple of years in a Lincoln-Mercury dealership as a tech before my career as an air traffic controller, and did several hundred  alignments.  All he did was set camber and front toe. He didn’t bother to try to correct the rear toe, which is out of spec. Why?  Probably because he didn’t know how.  Rear camber is mostly built in to ride height, but can be changed a little by adjusting the springplate  to trailing arm relationship.  

On my CMC, adding the shims was not as simple as it might seem.  My bumper brackets attach to the beam and rotating the bottom of the beam forward moves the outer end of the bracket up requiring adjustment.

Also, my car has fiberglass panels attached to the bottom of the bumper brackets that are glassed at the top to the underside of the fenders.  I had to change the attachment of the panels at the brackets.

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