Durometer Overview

Didn't your Gatorbacks feel better when they were brand new? After about 12,000 miles, did you feel like you were sliding around a lot more than when they were new? Does it seem like you had good tread wear for the first few months and now it seems like the tread is disappearing overnight? How come some people say they are garbage OEM tires. Well it could be that your tires are drying out. Just like a sponge dries out, your tires naturally loose their moisture.

There is a tool that will measure how spongy your tires are. It is called a Durometer. Unless you have some high dollar race tires where they actually print the Durometer readings on the sidewall, you will be limited to using the Durometer for comparison. For example you could take the Durometer reading of the tires when they were new and then you could compare later readings to see how much they are drying out and getting hard.

The Durometer is a simple spring loaded probe that when pressed against the tire, will deflect a meter and you can read the softness of the sample area. But don't mistake simple of cheap. Most Quality Durometers range in the hundred of dollars and are very precise pieces of test equipment.

You must apply equal pressure to the durometer each time you take a reading. If you press the durometer down very hard one time and then very soft the next your results will vary due to the uneven hand pressure.

You must also take a measurement quickly and be consistent when taking readings. If you place the durometer on your tire and leave it in the same spot for several seconds the rubber will deform, giving you a false reading. The rubber conforming around the durometer-testing probe will create the false reading.

When taking durometer reading the tire should be mounted on the rim with the proper air pressure. This supports the tread to make your durometer reading more accurate. Remember a durometer is a pressure sensitive device. Speaking of accuracy, two people could use the same durometer on a tire and get different readings based on how much pressure they applied to the durometer.

Using a durometer on a tire at room temperature is less than desirable. Ideally you want to test the durometer of your tire at the temperature the tire is going to see at the track. Manufacturers use compound heat curves to help them predict how a compound reacts during competition. Manufactures use scientific instruments but you can check the heat curve of your tire at home. To chart a heat curve you need a pyrometer and a durometer, Take a durometer reading at room temp, record the temperature and durometer reading. Heat a spot on the tire with the heat lamp, while keeping tract of temperature readings using the pyrometer. Take durometer reading every 20 degrees.

Ok, that's great. You have now learned your tires are as hard as rocks and getting worse by the day. To top it all off the tread is going to start to vaporize because it is so hard. So what can you do about it, other than find a rich uncle that owns a tire store?

You can chemically treat your tires and add the oil based moisture back into the tire. There is a product called Formula V Traction Treatment. Treating your tires with FVTT will allow your tires to return to their correct softness. You can not make it softer than it was originally but you can bring it back to the same standard.

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