QuestionThere are standards for wheels/rim (e.g., TUV, DOT, JWL,VIA,etc.) and tires (load ratings) but I have seen nothing that relates the strength of the combination of these two coupled elements. By strength I mean from impacts such a potholes under street conditions and for racing. I am particularly interested in alloy wheels especially between forged and cast rims. Is there anyway to obtain a quantitative measure of strength using different tire(@manufacturers operating conditions) and wheel combinations. I suspect the answer is no. Thanks for your time.
Later, ken
AnswerKen,
I need to explain this by starting at a different point.
There are indeed standards for both tires and rims. The standards are based industry testing methodologies at the time the standards were put in place - originally 1966 - and subsequent updates. The standards are MINIMUMS and no grade is assigned - except to say they either have to PASS or FAIL.
The tests are designed to test only the one component - not the combination.
My engineering sense tells me that rims can be made in both forged or cast (or wheel formed) and pass the minimums successfully - and apparently there are some of each available today. In fact, I'll bet that rims don't need to be made of any particular material to be able to pass the tests.
For example: Carbon fiber rims. In theory they ought to be incredibly light, but I have heard they shatter on impact instead of deforming the way some metals do. So the rim would be OK until there is an accident, then they could be very dangerous (expanding gas can have a lot of energy to release.)
Nevertheless, I think a carbon fiber rim could be designed to successfully pass any test put in front of it.
But there is one thing I am sure about: No amount of persuasion is going to convince a tire or rim manufacturer to divulge how much MORE than the minimum the tire or rim is designed to withstand.
So unless you want to do the testing yourself, I'm afraid you won't get the answer to your question.
