Diamond Back Tires


The Two Whitewall Manufacturing Methods

There are really two ways to make a whitewall radial tire. You can do it while you’re actually making the tire or you can add the whitewall to a finished tire as a final step. Remember, white rubber is just ornamental and has nothing to do with strength or performance. The advantage to adding it after the tire is made is that you can put a whitewall or color stripe on any tire you want, including 17", 18" and 20" tires — and with much tighter quality control. The versatility is endless and tires are all current production. This is how we do it at Diamond Back. We’re simply the "final step".


Scuffing The Tire

We start by mounting the new tire on a special machine that spins it at high speed. Using our own special attachments, we rough up the sidewall surface so it’s no longer perfectly smooth. The tire then goes on to where a special bonding agent is applied to the sidewall area that prepares the tire for the vulcanization process.

Because of the accuracy of our preparatory machine, and because it turns at such a high RPM, any abnormalities of the tire can be spotted immediately. Because we use major manufacturers our rejection rate is near zero.

Computerized Building

We have recently completed the installation of our new CIMA 850 sidewall builder. This machine is state of the art! It is totally computerized and can be programmed for total building perfection. Accurate building is essential and this machine will eliminate the most difficult steps in this process. It will accurately align the white rubber at the correct distance from the tire’s bead and will automatically stitch the white rubber to the correct radius or curvature. It will stop and cut the white rubber at the correct distance and the correct angle and it will totally eliminate the splice, or where the two ends of the white rubber come together.


A whole section of our plant is devoted to the vulcanization equipment that makes the whitewall a permanent part of the tire. Because the vulcanization process is so effective, if you tried to separate the whitewall from the tire afterward, the tire itself would become damaged. It's a marriage that lasts forever…a very permanent bond.

Our biggest competitors tell folks that Diamond Back's whitewalls are "glued on". They’ve even told people they’re painted on and even “ground out.” They say this to make us look foolish, so you’ll think we glue whitewalls onto tires using contact cement. It's not a true thing to tell people but at least now you know that vulcanization isn’t “gluing on”. It’s the process every tire company uses to build tires. Remember, our competitors don’t sell genuine brand names but rather, the "licensed" tires that they have made with the old molds.

So if you forget everything else, just remember that once the whitewall is vulcanized to the tire, it's on there forever (just try pulling one off the tire sometime).

Trimming The Whitewall

After vulcanization, the material has to be trimmed to the exact desired width, depending on what you order. Whether it's a 22" whitewall for a '57 T-Bird or a 32" whitewall for that big 40's classic, it makes no difference. The fronts and rears can be matched in whitewall width even if your tires are different sizes (as with hot rod big & little combinations). That's the nice part about trimming each whitewall or redline to order.

All of our finishers are equipped with lazer guides so that all widths are held to close tolerances. Once the trimming is complete, a series of finishing steps in the final process makes them nice and smooth.

Another advantage to high speed finishing is that it immediately shows us if there’s any kind of problem with the tire’s trueness (runout). The operator can spot it right away and he simply rejects the tire. It seldom happens.

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Diamond Back Tires

Diamond Back Classic Tires
Conway, South Carolina