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Discussion Starter · #1 · (Edited)
just had them put on today with adr spartains 18x8.5 on all four coners. what should the air psi be? on the tire it self, it says 50psi max. they got me about 46 on front pass and 50 back pass. i did not check the other 2. some advise plz. went about 120mph and was shaking. i drove 5 miles for test run. got home and checked 2 were at 45 psi 1 was at 46 and the other was 50:willy:
 

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EEZ GOAT said:
just had them put on today with adr spartains 18x8.5 on all four coners. what should the air psi be? on the tire it self, it says 50psi max. they got me about 46 on front pass and 50 back pass. i did not check the other 2. some advise plz. went about 120mph and was shaking. i drove 5 miles for test run. got home and checked 2 were at 45 psi 1 was at 46 and the other was 50:willy:
I think the shaking problem is more of a balance problem than air pressure. Did they balance the tires when you had them mounted? The other thing, it could be a bad cord in the tire causing an imbalance. I'd take it back to them saying this happened at a lower speed (70 mph), or they'll give you the "you shouldn't drive that fast" excuse.
 

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Toyo recommends setting tire pressures per OEM recommendations:
http://www.toyo.com/tires/tire_basics/inflation.html

So... 46 to 50 is pretty high, even for hot. When I've run street tires on the track, I set them for about 32 front, 30 rear and can heat them up about 10 psi to about 40 psi front, 38 psi rear or thereabouts (Vette numbers using Kumho Ecsta MX street tires which are slightly softer than the Toyo T1Rs).

Your balance may be off due to the high pressure but I doubt it. What is also possible is that due to the water used to get the tire on the rim, the tire can rotate on the rim after being mounted, which obviously will mess up the balance. I mark my track tires with chalk at the valve stem the first time I take them out and check the chalk vs valve stem position when I come back in. If it has moved, I have it rebalanced. :cheers
 

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EEZ GOAT said:
i did take them back and had them rebal, and he said it came back at 0. it happends at low speeds to. i think i will let them take it for a ride with me in the car pass side. it do have a 1yr warrnty on defect
Make sure they're doing a dynamic balance and not a static balance. If your wheel have a large lip on it some shops will attempt to do a static balance on them to compensate for the lip width. But that normally doesn't completely get rid of the side to side shaking of the wheel. Also some tires will have a small painted circle on the sidewall. That circle need to line up with the valve stem for achieving a better balancing (if I remember correctly). Check out the link below for more understanding on balancing.

http://www.discounttiredirect.com/direct/brochure/info/tmpInfoBalancing.jsp
 

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Discussion Starter · #7 ·
6QTS11OZ said:
Make sure they're doing a dynamic balance and not a static balance. If your wheel have a large lip on it some shops will attempt to do a static balance on them to compensate for the lip width. But that normally doesn't completely get rid of the side to side shaking of the wheel. Also some tires will have a small painted circle on the sidewall. That circle need to line up with the valve stem for achieving a better balancing (if I remember correctly). Check out the link below for more understanding on balancing.

http://www.discounttiredirect.com/direct/brochure/info/tmpInfoBalancing.jsp
when i took to them for my rebal, they said i need to get a high speed bal:confused
 

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EEZ GOAT said:
when i took to them for my rebal, they said i need to get a high speed bal:confused
Some shops refer to a dynamic balance as a high speed balance. They cost a little bit more than a standard (static balance) because it's more time consuming. Most tire shops do static balances because they're trying to get as many tires out the door as they can. So spending 30 minutes to balance tires compared to 10 minutes is money lost to them. If the shop you're at is telling you to go elsewhere for a high speed balance then that proves my point because they don't want to waste time/money doing it. And I'm sure their balancer can do a dynamic balance for you. Most balancers that I've seen can. Have you asked them to do it for you? If they say "No" ask "Why".
 

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Discussion Starter · #9 ·
6QTS11OZ said:
Some shops refer to a dynamic balance as a high speed balance. They cost a little bit more than a standard (static balance) because it's more time consuming. Most tire shops do static balances because they're trying to get as many tires out the door as they can. So spending 30 minutes to balance tires compared to 10 minutes is money lost to them. If the shop you're at is telling you to go elsewhere for a high speed balance then that proves my point because they don't want to waste time/money doing it. And I'm sure their balancer can do a dynamic balance for you. Most balancers that I've seen can. Have you asked them to do it for you? If they say "No" ask "Why".
he tells me that the high speed bal they dont take the tire off the car i guess they put it on a roller. and bal tire and brakes. but i will put my old ones on and drive to c if it is really the new shoes and have them drive on the hwy with both sets and let them c the diff:cool
 

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EEZ GOAT said:
he tells me that the high speed bal they dont take the tire off the car i guess they put it on a roller. and bal tire and brakes. but i will put my old ones on and drive to c if it is really the new shoes and have them drive on the hwy with both sets and let them c the diff:cool
Good luck.
 
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