Gary Z

My car is not particularly heavy or quick (3400lbs, 12.9 seconds, 1.9 second sixty) but my driver’s side wheel slipped in the tire. The wheels are 15x8.5 inch Convo Pros with 275/50/R15 MT Drag Radials. Tire pressure was 22.0 psi! The Passenger’s side wheel did not slip. This happened on the first or second quarter-mile run on these tires. The guy who mounted the tires really slathered on the lubricant. My hope is that this was only a case of the wheel seating itself more solidly and that I can try lower pressures without it slipping again. How reasonable is my hope?

T6Rocket

I have had two sets of DR's turn dramatically on the rim - 8" one time. Both times were within a few days of having them mounted. After that, they got a LOT better.

The longer they are on the rims seems to help.

Al

NRC-Motorsports

it depends on how they mounted them they should have been mounted dry,[acouring to MT] so mounting places coat the bead to get the tire on easier,now that causes tire to slip,if it persists,brake the bead and brake clean the wheel and bead,bob

Gary Z

Thanks guys. Until I’m in the tens , I would be embarrassed to show up with bead screws. It is good to learn that they shouldn’t be necessary.

s346k

iTrader: (4)

my rims spin inside the tires on launch, too. i have cast 2000 z28 rims with 255/50/16 bfg drag radials mounted on them. i was running 15 psi in them at the time, and on a 1.85 60' launch, you can actually SEE the rim spinning inside the tire (via pictures being taken that night). wtf? the car spun very bad on that launch, hence the 60' (i have a 4k stall which i have cut 1.6x 60s on). the bfg DRs wrinkled very well, but the rim could be seen inside spinning. i thought this was kind of odd. i ran a 12.4 @ 109 i believe on that pass.

edit: the tires have been mounted on the rims roughly 9 months, but rarely are on the car.

Gary Z

I don’t want to say that your wheels did not spin in the tires but I do know that motion pictures are not reliable evidence. The effect that causes movie wagon wheels to appear to turn backwards needs to be considered. The simple way to determine slippage is to put marks on the wheels and tires and check later for misalignment.

s346k

iTrader: (4)

after seeing the picture i later confirmed using a crayon. anytime something like that is noticed, investigation is inevitable!

Pro Stock John

iTrader: (34)

How much are they moving?

Gary Z

The marks on the tire are displaced approximately 6-inches from the marks on the wheel. I assume the slip was less than a full rotation because the tire did not deflate and there is no evidence of any damage.

z-ya

iTrader: (1)

My 275x50x15 mickeys on bogarts slipped about 2" each pass at 18 lbs,knocks the balance all to hell.

Gary Z

Excellent point! This is a problem I had not considered. Thanks, Gary

1BADAIR

iTrader: (1)

mine don't move at all