This last weekend, somebody borrowed my MAXMOD Tire Durometer.....When I got it back, a very well known World Champion sent it back to me with a message that it doesn't read correctly......HMMMMM
So, I tested it against a my tires, and sure enough, its reading of my Jaco 42's came up 52, on 2 different sets of tires, new and used.......
I went in search of finding where to send it to get it "factory" calibrated and couldn't find where it was made to send it back, but I came accross a post on Petitrc.com in the forms that was writen by Jack, (Jaco tires).
If you have a Maxmod or similar durometer you will probably get a 5-10 point higher reading. This is fine, as long as you use the durometer to COMPARE the tires YOU run. Do not try to compare to other drivers or to our numbering system. The Maxmod is not consistent or accurate enough compared to a $600 Shore Type C. It does, however, serve it's purpose of grading your own tires in relation to each other very well.
So, I did some searching and found another of his posts that read:
Whatever you do, DON"T GO BY DUROMETER READINGS ALONE. They mean NOTHING when comparing tires from different "Families". I can give you 4 different tires that read 30 on the durometer. Only one will work on the rear... one will do donuts and spin out, one will make you push to the wall, and the other will wear out in 2 minutes. This is the most common misconception regarding tires I see.
Now that I'm still confused, but not as much, the only good use of the durometer is to match tires up, by shore readings, not actual shore of the tires.
Can anybody answer a few questions:
Do the tires have to be the same size to take readings?
Does "family" mean batch, or brand?
Does anybody know where to send the Durometer to get calibrated?