I bought a V last month and the tires had a red dot on each one. A coworker's husband works for Michelin and she said she thought the red dots meant they were defective. Any ideas?
Not defective. There is a post in here about that I just can't remember what the meaning was. I think it was a balance point or something... They disappear after a bit. edit: Here is an explanation I found: Yellow=Light Red=High Aligning the red mark with the low spot on the wheel(usually marked on wheel with white dot) is the best method for mounting tires. This makes the assembly more uniform and helps limit the RFV (Radial Force Variation). If you have expieriance with a newer high line tire balancing machine, it will "OEM Match" tires for you, which basically means matching the uniformity of the wheel to the uniformity of the tire. this is very important to to when mount very stiff or high performance tires, as it will limit tire vibrations causing shimmy and shake."
Don't worry about it. Your co-worker's husband is wrong. Toyota has enough trouble without adding a defective tire scandal to their stack of stuff to fight in court---and the OEM tire supplier (Bridgestone for my II) would never sell blems to a manufacturer, even if they tried to buy them. 100-percent fertilizer.
The red and yellow dots are for mounting and balancing, as mentioned above. I work in aviation and our tires have them also, we have to align the red dot with the tire valve when placing them on the wheel rims. The red dot is usually 180 degrees out from the heavy spot on the tire. Placing the red dot in line with the valve in theory will put the tires heavy spot opposite the valve and aid in naturally balancing the tire. The same is true with automotive tires. It may even be more critical on a car due to the added weight of the TPMS sensors at the valve. If aligned at mounting it may save from having to add excessive balance weights. Balance When a wheel and tire is rotated, it will exert a centrifugal force characteristic of its center of gravity. This cyclical force is referred to as balance, and a non-uniform force is referred to as imbalance or unbalance. Tires are checked at the point of manufacture for excessive static imbalance and dynamic imbalance using automatic Tire Balance Machines. Tires are checked again in the auto assembly plant or tire retail shop after mounting the tire to the wheel. Assemblies that exhibit excessive imbalance are corrected by applying balance weights to the wheels to counteract the tire/wheel imbalance. To facilitate proper balancing, most high performance tire manufacturers place red and yellow marks on the sidewalls to enable the best possible match-mounting of the tire/wheel assembly. There are two methods of match-mounting high performance tire to wheel assemblies using these red (Uniformity) or yellow (Weight) marks.[24] Above copied from Wikipedia. Tire - Wikipedia, the free encyclopedia Shame on the gentleman from Michelin for being uninformed and misleading to you. If you look on Michelin's aviation tire web site, you can find allot of resources and information on tires. They have Tire Expert Training Program Levels 1&2, it will explain and tell you everything you ever wanted to know about tires and you get a certificate of training if you complete the courses and send back your tests. Michelin Air: The very best in aviation tires.
