any ideas on how to deal with this and what this will cost?
You must be new to low profile tires...you're driving on 21" rims and low profile summer performance tires .. stuff like this is expected to happen. In a nutshell, they are just not practical. Kind of like the impracticality of the fuel efficiency on a Bugatti Veryon (which is "3". yes, that is "3 miles per gallon".) IMO, due to the higher risk of blowouts (or rather, rapid deflation after hitting a pothole), I don't find these tires safe either. I would never feel safe driving my family around on these. While I won't go as far as to say that I feel these tires are outright "unsafe", the truth is that they are just more susceptible to damage and risk of blow outs. THAT is what I find unsafe about them.
On the technical side, "low-profile" means the sidewalls are short. This makes the sidewalls firmer, and less likely to bend and deform on turns, which results in better handling. These short sidewalls on low profile tires are very fragile and vulnerable to road hazards such as potholes and other obstructions (as you just encountered). In the winter, it is like driving on ice skates. In addition, the typical lifetime expectancy for the treadwear is 6k-10k miles before falling below 4/32" and needing replacement.
To add to this even further, the tires are noisier and the ride itself is more punishing because there's less sidewall rubber to absorb the bumps.
This is no "secret" either. Officials from Goodyear, Michelin, and Bridgestone will all admit to this.
"They are more susceptible to pothole damage," said Bill VandeWater, Bridgestone's consumer tire products manager, in Nashville. "They don't have as much give before the tread contacts the rim. There isn't as much deflection capability as a taller tire."It is meant for those people who see the freeway exit sign that says 40 mph, and they get that gleam in their eye and think: I bet I can do it at 80 mph," VandeWater said.
Even auto manufacturers and government officials admit they are impractical:
Volkswagen's suggestion. "Avoid driving on roads with potholes, deep gouges or ridges," it tells owners of cars equipped with these tires.
"My observation, other than styling, is why have them?" asks Clarence Ditlow, executive director of the Center for Auto Safety in Washington, D.C. "My advice to consumers is don't buy them."
There are 0 ... Z-E-R-O ... benefits from low profile tires. For some people, as impractical and unsafe as they are, people view them as aesthetically pleasing and somehow that is more important to them than safety and cost of maintenance. They are even worse for you in terms of fuel economy, or in the M.S. world, the 21" low profiles will
negatively affect your EV range.
If you don't want to deal with roadhazards and rim damage, blowouts, etc, in addition to regularly replacing your tires every 8-10k miles for treadwear alone, then I
STRONGLY suggest replacing all of them with the 19" rims and some good 19" Michelins. This will also improve your range. You won't have the pothole/obstruction problems anymore, and the treads should last you a good 30k miles or more (as is probably what you're used to coming from whatever ICE vehicle you came from).
I leave with this - when you're driving 75mph, who gives a crap what your tires/rims LOOK like anyway? At 75mph, what matters is how safe and durable your tires are.
