There is a reason the smart has bigger tires on the rear......Google "moose test"
Very good and important point which everyone considering changing the original OEM set up to a drastically different one should take into consideration. We read all we could find on the moose test when it impacted Mercedes with the A-class back in 1997 that caused such alarm. Mercedes recalled the car, installed anti sway bars, changed tires and installed stability control allowing the A300 to pass the test.
My opinion for what’s its worth Mercedes didn’t want another A300 fiasco on their hands and took precautions by installing this combination which was thought to make the car understeer, but in reality with this setup in my opinion creates a drastic over steering situation especially on wet roads and tight turns, the front tires are useless.
This is what I believe through the experience driving my smart. It should not be considered a green light for anyone going with an all fours setup. They should use their own experience and read the results behind the tests and come to their own conclusions whether they are willing to sacrifice what Mercedes believe was safe verses their own driving ability.