New Tires

@Marshall, it certainly could be your tires, but without knowing how you drive it's tough to say.  Remember the this is a rear-engine car and proper technique is needed to get the most out of it.  The best philosophy is "slow in - fast out."  Do your braking before the curve and then accelerate through it, other wise the tail will most certainly try to come around on you.

IMHO Nankang tires may be the problem(as are all Chinese tires). Check the date code(you can find how to decipher letters/numbers online). Any tire that's 5 years old should be replaced.

If you can find a set of Sportrac5 then get them.

1972 pan should be IRS rear end, unless it was changed back to swing.

Even with the best tires, these things handle like the 1940s or 1950s.

Alignment settings are also important as are anti-sway bars(and a camber compensator if swingaxle rear).

I bet your CMC has been lowered from the stock bug sedan.  Usually by using one or (better) 2 beam adjusters welded into front H beam.  Dropped spindles are another lowering method.  When lowered, the car needs at least 1 (often 2) caster shims per side (ALB responded with details in another thread). These will keep the front from darting.

What's tire pressure?  Experiment with pressure around 20-22.  Worth checking and repacking front wheel bearings too.

A front and rear anti-sway (or camber compensator if rear is swing axel) will keep tires on the ground when fast cornering.  Most stock VW came with a thin front sway bar - most replace with aftermarket 3/4" one.

I would start with tire pressure. If it’s too high your already lower quality hard rubber tire won’t get the grip it needs. The pressure shouldn’t be above 22 thereabouts. And if your car is a swing axle I’d consider adding a rear camber compensator from CB Performance. That will help keep the rear wheels where they belong and not tuck under at all. If the wheels are tucking under a little you will lose some of the contact patch between your tire and the road reducing grip.

@DannyP i was waiting for a true authority to weigh in on this topic....which i am far from being...i just know a bit more as well as a bit less than others....my coupe is on a '74  beam front end & IRS pan...and has decent shocks & front & rear sway bars....and seems to enjoy 85 mph just fine on the freeway depending on road smoothness and sticks on corners OK (within reasonable sanity).....but you are correct...these cars are NOT GT3's and the nervousness is just the nature of the beast...as always IMHO

I should have mentioned that low profile tires (60/65) handle better than the original VW profile (80/75).  Summer tires are stickier than say all season tires too.

I have never been told but why are the rec tire pressures so low (22 PSI).

It's the lowest I have ever hear of.

@WNGD posted:

I have never been told but why are the rec tire pressures so low (22 PSI).

It's the lowest I have ever hear of.

These cars (Speedsters as well as Beetles) are not heavy and are lightly sprung.  IIrc, factory air pressure specs are 18 or 20 psi for the front and 22-24 for the back.  Remember, this is for the most comfortable ride, and performance driving will need to be slightly higher.

@ALB posted:

These cars (Speedsters as well as Beetles) are not heavy and are lightly sprung.  IIrc, factory air pressure specs are 18 or 20 psi for the front and 22-24 for the back.  Remember, this is for the most comfortable ride, and performance driving will need to be slightly higher.

But not much. I run 23-28 F-R on my Spyder for AutoX.

The cars are light. We could actually run lower pressure since some of us are hundreds of pounds less than a stock Beetle. But the problem then is keeping the tire from rolling off the rim. You need enough pressure to keep the tire's shape, but not so much to make the ride hard and bouncy.

You need to keep the tire just stiff enough to hold both the contact patch and the sidewall stiff enough.

Modern belted radials have stiffer sidewalls than the bias ply tires from when this suspension was designed. That is part of the 5 year replacement rule, as the already stiffer tires only get harder with time, both in the tread and in the sidewall, reducing both stick and ride compliance.

Greetings,

A question regarding over winter storage, tire pressure and “flat spots”.  BTW, I checked my tire pressures as previously recommended.  All were approx. 23.

I’ve been told that some of my vibration at speeds over 60 or 65 may be due to parking the car for too long periods without moving it.  The wheel gets a flat spot?

Is this true? Does this happen? Could I help avoid it by increasing the tire pressure temporary during low use periods?  For instance, I’m leaving for a two-week trip Saturday. Should I raise the pressure to whatever is recommended on the side walls while gone?

In fairness, I really don't let my car sit for really long periods of time.  I drive her whenever dry, recent rains have washed the salt residue off the streets and if much above 47. But there are times when she just has to sit for several weeks without use until the weather gods and schedules allow, like over the next 2 weeks.

Is there any truth to this?

Marshall

I have heard that, for long term storage, you should always over inflate the tires, to help prevent flat spots, and to prevent sidewall damage.

@DannyP wrote- "You need enough pressure to keep the tire's shape, but not so much to make the ride hard and bouncy."

Your technical writing (and command of the language) I can only aspire to, Danny!

@Marshall- While developing flat spots when sitting a long time may have been an issue with bias- ply tires, with today's modern radial construction and rubber compounds it's (I don't think) something to worry about.  I started driving in 1972, bought my first car (a '66 bug) in 1974, it had bias-ply 5.60-15's (close to the same size as a 165-15), put flared fenders on it with G60-14's and D70-14's on it, for the year and a half (or so) that I owned it never found it to be a problem and didn't notice it on my dad's Ford station wagon either.  I did hear those stories about tires from the '50's , but was under the impression that it was because of the cruder rubber compounds used and that once they warmed up the flat spots disappeared.

Short answer- I don't think you have to worry about it- you could overfill the tires a little if you know it's going to sit for a while, but be sure to remember to adjust pressures before taking it out (otherwise, you know, like Danny says, "it'll ride hard and bouncy").  Some guys, when putting their hotrods away for the winter will put them up on jack stands and if may be a valid concern if the car is shod with the older style tires, but with radials, again, I don't think it's anything to worry about.

Unless your garage/car storage place gets really cold- there are some summer performance tires today that shouldn't be driven on when temps are below 50? 45? 40°??? F.  Even some all season tires get harder (and don't handle nearly as well) at just a few degrees above freezing these days.

Hope this helps.  Al

@ALB Hey Al, why don't you go drive your Speedster LOL!

Conversely, I can get in mine and drive it whenever, even if it is freezing out!

If I only had one set of tires and were leaving the car all winter, I'd vote for jackstands. As Al says, there are tires that should not be driven on or even have weight on them colder than 40F.

My summer tires are stored in my basement, away from heat, moisture, and light, at about 50F, lowest I've seen down there is 45F. I have a set for the Spyder and another set for the Cayman.

The Spyder sits in the garage on storage wheels: old steelies and worn out tires, but on a battery tender/maintainer/float charger. Full tank of gas. Oil gets changed in the spring.

I have noticed some out-of-balance on cold mornings with 40-45 series low profile all seasons. That is for about 5 miles until they warm up to be a little more pliable. Shouldn't really be an issue though with 65 and taller tires that our cars run.

@Marshall

Yes, depending on the make of tire and its' composition, sometimes they do get flat spots on the bottoms and then rumble for a while when you first take them out.  This is more noticeable at lower outside temps when the tires are stiff.

Over-inflating them while they sit has been mentioned by a lot of folks, especially on the Porsche forums.   You can also leave the tire pressure alone but put the car up on jack stands for the winter (our winter is a bit longer than yours here in Massachusetts) or, if you have a lift, just raise the car up so the tires just clear the floor and leave it there or raise it to the first safety stop.

Greetings.
Thanks to all for all the advice.
I’ve got Nankang? radials on now.
Here’s a summary. Most agree that upgrading to a more expensive tire is advisable. I’ll be sure to keep my pressures low 21 to 23 psi. Will check that alignment. I’ve hit a couple of potholes. Can’t jack the car up as it’s parked in my driveway and used spontaneously. But I will increase my tire inflation during the winter when the car is driven a lot less frequently.  The more Expensive items regarding front end and rear end adjustments and changes will have to wait.

Thanks again.

Marshall

I don't know if it is clear above that the front tire pressure needs to be lower than the rear.  I run 18 front and 28 rear.

Be sure to have something like plastic strip or 2x8" PT wood between your tires and the driveway.  Tires will absorb moisture from the ground, stones and even concrete surface.

Should have mentioned earlier - but check the "rag joint" for your steering column to the steering box.  Some use the red poly material which cracks and is dangerous.  The OEM style reinforced rubber joint is best but even it needs to be checked periodically. Also check the compression piece for cracks.

Is this "Be sure to have something like plastic strip or 2x8" PT wood between your tires and the driveway" for storage?

I also learned that it is bad to store a transmission of concrete.  The case corrodes.

Yes for long term storage.  My dad always told me not to store batteries on concrete.  I think that is old myth based on when the batteries had rubber (and not plastic) housings.  Regardless, I still store them in a plastic marine case on a PT 2x6".

Moisture really eats magnesium alloy products.  I've got old VW block that had a bad head (#3 exhaust valve broke off) - water got in case and the area around the sump plate is corroded.  I was told it could be used - but even new they seem to leak oil there.

@Marshall- what no one has mentioned about tire pressures- experiment- try a little higher and then a little lower, to see where you like it best.  And what @WOLFGANG said- check the expanded metal compression piece if your steering column has 1 (we have seen them crack) and flex joint regularly- before every drive if your rag joint is red poly- they go from fine to really torn up very quickly, really are the wrong material for there- maybe the best plan of action is to replace it with an original piece, as they're much more durable _{and we don't want to have to be talking about how he was a really nice guy and had just gotten his Speedster in tip top shape and it's a real shame and what's worse there was nothing to salvage....}

.

@Marshall posted:

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...I’ve been told that some of my vibration at speeds over 60 or 65 may be due to parking the car for too long periods without moving it.  The wheel gets a flat spot?

Is this true? Does this happen?...

Marshall, I always look for simple checks before I start ripping things apart or losing too much sleep.

If you have to park the car for a few weeks (when you're not away on a trip), try rolling it forward or back a foot or so every few days so the tires aren't parked on exactly the same spot for the whole time. If that fixes it, your tires are flat-spotting. But even so, flat-spotted tires should sort themselves out after a few miles of driving. If they don't, toss them.

I had some Kumho tires on a Miata in the late '90s that flat-spotted when parked for a while. Eventually, no amount of driving on them would make the vibration go away.

If the vibration can be isolated to one wheel, or to 'front' or 'back', a simple tire rotation will tell you if the problem is with the tires.

Nankangs are often fitted because they're available in hard-to-find sizes, but their reputation is not sterling.

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Tires on concrete are okay as far as I know. Curved wheel dollies are a good bet if you don't want to jack it up. They do prevent flat-spots.

Any metal on concrete is not a good idea. Concrete is a moisture magnet, be it magnesium, aluminum, or steel. I won't store anything I care about on concrete. Plastic tubs seem to fare well and insulate your stuff.

Having said that, I still will only store batteries on a block of wood if they're not in a car.

Since we're talking batteries, I use a float-type battery tender on all my stuff.

@DannyP posted:

Having said that, I still will only store batteries on a block of wood if they're not in a car.

I started buying Milo some frozen raw elk/deer meat last year. It comes in styrofoam coolers that are perfect for batteries. I currently have my Mercedes, Porsche, and Ducati batteries in them on Battery Tenders.

I scanned through the thread pretty quickly but I seem to recall some advice re: wandering front ends that Speedsters need a couple of extra degrees of castor vs what a standard VW beam has. Am I mis-remembering?

@dlearl476 posted:

I scanned through the thread pretty quickly but I seem to recall some advice re: wandering front ends that Speedsters need a couple of extra degrees of castor vs what a standard VW beam has. Am I mis-remembering?

You are remembering correctly.  Stock caster spec for a type 1 is 3° 20' + or - 1° (taken from chapter 6, page 33 of the orange Bentley manual).  Gordon Nichols (and others) recommend and run at least 5°.

After you sort out and (if) you determine its the tires.  Get the Vred Sport Trac 5s while you still can.  I ran 265hp into mine and they are fabulous.  They are also quite runners.   No flat spotting during winter storage either.

https://www.tirerack.com/tires...HR5ST5&tab=Sizes

But Tire Rack DO NOT recommend keeping any weight on them at 40F and below.

So I don't do that.

@DannyP posted:

But Tire Rack DO NOT recommend keeping any weight on them at 40F and below.

So I don't do that.

^ What Danny said, I stored in a heated garage. Maybe Danny is referring to driving? Yes, no Driving in cold weather with summer tires.

@Marshall posted:

Greetings,

I have Nankang radials on my car.  I told the man who cares for my Speedster that she wants to slide (more like the rear end wants to slip) on sharp corners much above 40 mph.  Also, that she dodges a little left and right on straightaways starting around 60 or 65.  But the corners are the real issue.

Marshall

So I'm a little confused about this. Sharp corners, meaning?

A right-angle intersection?

Or a curve that is rated at 25mph but you're doing 40?

@Marty Grzynkowicz posted:

^ What Danny said, I stored in a heated garage. Maybe Danny is referring to driving? Yes, no Driving in cold weather with summer tires.

Read this, this is the specific info on Sportracs on the Tire Rack website:

https://www.tirerack.com/tires...tireModel=Sportrac+5

And I quote:

"Note: Tires exposed to temperatures of 20 degrees F (-7 degrees C) or lower must be permitted to gradually return to temperatures of at least 40 degrees F (5 degrees C) for at least 24 hours before they are flexed in any manner, such as by adjusting inflation pressures, mounting them on wheels, or using them to support, roll or drive a vehicle."

Ran into this tire comparison (a little old 2016) but thought others might find it informative.
https://www.cinturato.net/imag...assic-tyres-0716.pdf
Does anyone have real-world experience with the Pirelli CN36?

They are the best,. the only problem is the cost.  They also look the best on a vintage car.  They have the proper sidewalls for a vintage suspension.  Porsche N Spec. Most guys wont drop $329 per tire on there replicas though.

https://www.lucasclassictires....-CN36-p1857015n4.htm

And on a members original 356A Coupe.

Don't they have a wear rating under 200?

Most guys drive these things like 1,000 miles a season; so, they will dry out before they wear out.   Road warriors like you are better off with the Vreds.

200, 300. Whatever it takes LOL!

A thousand miles a season?

Why have a speedster?