Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB - View Single Post - Put on new rear tires, now my car handles terrible! WTF?

NOHOME · 12-03-2014, 10:51 AM

Very slight mis-match in tire diameter. Worn fronts and worn rears might have just slipped by, Worn fronts and new rears don't make it under the radar. There is a reason why some tire dealers wont sell anything less than 4 new matched tires for some cars.

On a 24 inch diameter tire, a 1/8" diameter mismatch means that the tire with the 24.125" diameter with a circumference of 75.8" will turn 835.9 times per mile while the shorter 24" diameter tire with a circumference of 75.4" will turn 840.3 times per mile.

IF the car is keeping track, it will care about the 5 rotations per mile.

There is a reason I have not sold the MGB yet...not entirely sure I am going to be happy with this level of adult supervision when I play with my toys.

12-03-2014, 10:51 AM	#21
NOHOME Senior Member Join Date: Jun 2012 Drives: RAVEN Location: LONDON ONTARIO Posts: 795 Thanks: 86 Thanked 800 Times in 346 Posts Mentioned: 12 Post(s) Tagged: 2 Thread(s)	Very slight mis-match in tire diameter. Worn fronts and worn rears might have just slipped by, Worn fronts and new rears don't make it under the radar. There is a reason why some tire dealers wont sell anything less than 4 new matched tires for some cars. On a 24 inch diameter tire, a 1/8" diameter mismatch means that the tire with the 24.125" diameter with a circumference of 75.8" will turn 835.9 times per mile while the shorter 24" diameter tire with a circumference of 75.4" will turn 840.3 times per mile. IF the car is keeping track, it will care about the 5 rotations per mile. There is a reason I have not sold the MGB yet...not entirely sure I am going to be happy with this level of adult supervision when I play with my toys. Last edited by NOHOME; 12-03-2014 at 11:34 AM.