K/O wheel and tire balancing question

[Tim D.]

I am finishing a complete restoration on my 64 convertible. I have had my wheels and tires balanced twice by my local NTB store and still have vibration. I don't know what kind of a machine they used. I am running on new Corvette America Repo KO's (bolt on) and BF Goodrich Silvertown 6.70-15 4 ply tires. All parts on car are NEW! I know it is the wheels/tires because I installed a set of original wheels and radials from my friend's 64 and the vibration was gone.

My question...I am considering going one of two ways to get these balanced and have a smooth ride....I have heard GREAT things about both.

1st method: I called Corvette America and they informed me the wheels are "lug centric" as opposed to "hub centric", therefore they need to be balanced on a Hunter BSP-9700 Road Force Balancer WITH the use of a Haweka flange plate adapter to keep the lug centric wheels centered in place while on the balance machine AND a tech that knows how to use the machine properly. I have seen the thread where John Hinkley shows his K/O's getting balanced with this machine...althought the adapter plate was not mentioned.

2nd method: go to this link: www.innovativebalancing.com and check this out. DYNA beads are installed through the valve core. It looks like they recommend 4 oz per wheel for my tires. They continuously roll around inside your tire and balance your wheels and tires even as the tire wears etc...it keeps the balance fresh every time you drive. A friend of mine uses these on his motorcycles and swears by them. He said it extended his tire wear life by 4,000 miles...he does a lot of road touring. He told a friend of his who couldn't get a good balance on his brand new truck and the guy said it is UNBELIEVABLE how smooth his ride is with the dyna beads.

Any thoughts, would be greatly appreciated!

Thanks,

TIm

[Rick A.]

Re: K/O wheel and tire balancing question

not to be a smart aleck, but you are expectin a smooth ride from bias-ply tires?????? I need to be smoking what you are!

[John H.]

Re: K/O wheel and tire balancing question

Tim -

If your BFG Silvertown 6.70-15's are Coker reproduction tires, they're probably out-of-round; take your wheels/tires to a shop that has a Hunter GSP-9700 Road Force balancer and they can check lateral and radial runout of the wheels and wheel & tire assembly independently, in addition to road force variations caused by tire construction that FEEL like they're out of balance. Go to www.gsp9700.com and use the locator to find a shop/dealer near you that has one.

[Tim D.]

Re: K/O wheel and tire balancing question

John -

Thank you very much for your help and information. You are a true gentleman and have helped me on numerous occations. I always value your knowledge and opinion. There are several shops near me that have the Hunter GSP-9700. Now I just have to find the shop that has a really good, experienced tech that knows how to use it properly. I will let you know how it all comes out.

Have a great evening!
Tim Dailey (50796)

[Jim L.]

Re: K/O wheel and tire balancing question

the wheels are "lug centric" as opposed to "hub centric",

If these are true knockoffs, that doesn't make any sense.

The lugs, or drive pins, are there to provide a way to transfer torque between the wheels and the adapters.

The cone of the KO spinner working against the inverse cone machined into the wheel provides an unavoidable self centering action as the spinner is tightened.

Since there can't be two centering mechanisms, there must be some slight slop in the fit of the drive pins in the wheels holes so the spinner cones and wheel inverse cones can do their jobs.

That said, the adapters would be lug centric, though.

Jim

[Paul J.]

Re: K/O wheel and tire balancing question

If these are true knockoffs, that doesn't make any sense.

The lugs, or drive pins, are there to provide a way to transfer torque between the wheels and the adapters.

The cone of the KO spinner working against the inverse cone machined into the wheel provides an unavoidable self centering action as the spinner is tightened.

Since there can't be two centering mechanisms, there must be some slight slop in the fit of the drive pins in the wheels holes so the spinner cones and wheel inverse cones can do their jobs.

That said, the adapters would be lug centric, though.

Jim

Jim, I believe that he said that they were the CA bolt on "fake" KO wheels.

Paul

[Bob R.]

Re: K/O wheel and tire balancing question

I put a set of the BFG tires on my 63 a couple of years ago. My friend is in the tire business and he balanced them for me. He told me they were about the worst tires he has ever seen to balance. These tires are made in small quantities and the quality control is not there. I mounted the tires on standard steel wheeels and I don't think your knock offs are the problem I think its the tires. My friend told me he spent 2 hours balcncing 5 tires most shops won't spend that much time. He also marked the tires that balanced the best for use in the front and the worst tire I put in the spare tub. You may have to find a shop that will spend a little more time on them. I get no vibration up to about 65 miles an hour.

[Tim D.]

Re: K/O wheel and tire balancing question

Jim and Paul -

Yes, these are "fake/reproduction" Corvette America 1964 bolt on with the KO cones and spinners not original Kelsey Hayes.

Tim

[Tim D.]

Re: K/O wheel and tire balancing question

Bob -

I too, suspect the problem is with the BFG reproduction 4-ply tires and not the CA wheels. I know 4-ply is a thing of the past vs the much improved ride and handling that radials provide. I just don't care for the look of radials on a 64. I know some guys have two sets of wheels and tires ...one for show (4 ply) and one for driving comfort (radials). Thanks for your input!

Tim

[Robert C.]

Re: K/O wheel and tire balancing question

Tim,

Use the pin plate adapter that you noted in your "1st method".

I always check the rims on my balance machine without the tires, you would be surprised how many
wheels are not too good. You spin them and you can see them wobble back and forth.......

You may very well have a wheel (s) that are off. Add in tires with poor Q/C and you'll have a mess.

For tires this size, generally you want your weights on either plane (inner/outer rim) to be less than 2 oz.

If you see alot of weight on your wheels, you have an issue. I think either Hunter or Coats (they mfg. wheel balancers) have noted 60% of wheel balance problems are attributed to not installing the tire / wheel assembly on the machine correctly.

I agree with that.

The "pin plate" is specified equipment by a number of current, late model car mfgs. to eliminate the center of the wheel being "off".

Not to mention tire equipment that is beat up. If your NTB is using centering cones and they are junk - well, that's a problem.

The Hunter Road Force machine will measure both wheel and tire runout. It's also smart enough (if used correctly) to tell a tech to offset a wheel / tire combination to help balance something questionable.

This assumes the "tech" at NTB knows how to use the machine in the first place.

The Haweka pin plate is a great tool, assuming they use it. Re-read what I just wrote.......I've balanced mid-years factory and reproduction knocks off to under .05 oz per plane. This is a "high accuracy" balance. Most machines do .25 oz.......whether the extra degree of precision I do is worth it may be questionable, but that's what I do.

"Chasing weights" on a machine tells me something is wrong with how it's mounted on the machine.

Like I noted, you can have a bad wheel and a bad tire, but the Hunter Road Force can measure all that.

Also, guys at these shops can bypass using the road force function, and I've seen that happen.

You can also bypass any measuring and spend hours chasing weights......measure, measure, measure.

If it helps, trying to get tire chains to use some of the xpensive equipment they purchase is the trick sometimes. Plus, the young guys mounting tires are trained by the guy next to him. If that guy doesn't know how to use the machine, he doesn't either.

[Tim D.]

Re: K/O wheel and tire balancing question

Has anyone tried the DYNA beads as an alternative? See the link above in my original question. Tim

[Robert C.]

Re: K/O wheel and tire balancing question

Tim,

These "self balancing" things have been around for years and never seemed to take off.

I mean, have you ever seen them on an ultra-expensive car from an OEM?

Stick with what the rest of the world does and you'll be fine.

Good wheels + good tires + good tire balancing equipment + everything done correctly = Happy Corvette !

Bob

[Tim D.]

Re: K/O wheel and tire balancing question

Robert -

Thanks for the valuable info. I really appreciate your input and knowledge. It sounds like the Hunter Road Force machine is the best way to go. I did talk with a guy at a local chain this morning and he showed me the Hunter RF 9700 they use. He said they have done a few mid-year Vettes and seemed to know his stuff. He said he would put his best tech on it and that it was time consuming etc and therefore could get pricey if they have to break down each tire to relocate it on the wheel, which I don't mind if it solves the problem. I think at this point the biggest trick is finding a tech that truely knows what he is doing and is willing to spend the time to get it right the first time. As we all know, it can get old throwing $ at these problems and not getting good results.

He showed me the assortment of pin plate adapters but didn't seem familar with the Haweka plate which made me a little skeptical.

Robert, where are you located? Does anyone have someone they could recommend in the St. Louis, Missouri area?
Tim

Tim

[Robert C.]

Re: K/O wheel and tire balancing question

I'm up in Ohio, so I'm sorry I can't help you. Off hand, I don't know the Corvette shops in St. Louis - but keep asking, someone will chime in.

Several companies make pin plate adapters, I own a Coats machine and use a Coats Pin Plate.

Each company (e.g Hunter, Coats, etc.) may have different size shafts on their wheel balancers, so a number of pin plates are available.

Haweka is fairly big, but NTB can very easily get equipment from the corporate side, so the managers don't actively
shop for equipment.

First thing, I'd have all 4 tires mounted on the RF, measured (rim, side to side and tire (side to side and lateral) and go from there.

If all 4 rims have some side-to-side runout - well that's the first step. How much side to side variation is acceptable
is another matter.

The loaded runout (e.g. how much the tire is "out of round"), I think the generally acceptable rule of thumb is .025 inches.

I have seen tires in the .019 to .025 range become hard to balance, but the Road Force can match a wheel and tire and
suggest how much to rotate the tire on the wheel to get an acceptable balance.

Now, whether the tech does is is the trick with all this. Just like using the pin plates......they can have a boatload of them sitting on a wall next to the machine, if nobody uses them - well, they are worthless to you.

Same thing with training. The Hunter RF i sa very expensive and sophisticated machine, but if you don't know how to use it - well, what good is it to you?

Also.......if you have a marginal tire / wheel, but the RF blances it ok, note it and mount it on the back.

If you have belts that are broken, shifted, etc. it will show up.

Overall, I would think Coker would stand behind their products, same for CA.

We have used mid-year repro KO wheelsfrom Long Island Corvette, all were fine.

Bob

[Jim L.]

Re: K/O wheel and tire balancing question

Jim and Paul -

Yes, these are "fake/reproduction" Corvette America 1964 bolt on with the KO cones and spinners not original Kelsey Hayes.

Tim

My mistake!!!! I missed that detail in the original posting. Then these wheels are lug-centric, as you were told.

Crawling back into my cave now.....

Jim