Tires with rubber build up after tracking
06-16-2010, 05:48 PM
#16
Rennlist Member
Thread Starter
i think what he's referring to is the difference in the wear on the outside shoulder. the top line (pictured) indicates overinflation - and the bottom line indicates that there was more tread contact with the surface.
as the day progresses in an event, typically you'll see tire temps go up, and if you don't lower the pressure, you're effectively running on less tire, in case case, probably an inch
as the day progresses in an event, typically you'll see tire temps go up, and if you don't lower the pressure, you're effectively running on less tire, in case case, probably an inch
06-17-2010, 03:16 AM
#17
Three Wheelin'
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as you go thru multiple runs and put heat cycles into the tire, you'll see different lines form that show where the tire heated and wore on that run. they'll be noticeable if they go from outside --> inside, meaning you want to lower a bit of pressure to get it optimal. sometimes, if tire pressure is too low, the wear will be to far onto the sidewall.
you're putting heat into the tires which means to me that you're having fun and the tire is doing what it's supposed to be doing. good for you!
you're on a slippery slope here
06-17-2010, 06:31 AM
#18
Still plays with cars.
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PS2 rear should be run at around 38 lbs hot on track.
06-17-2010, 09:34 AM
#20
Race Director
His tire wear looks fine.
Not knowing his alignment specs and tire temps we realy can't say much.
PS2's will roll over on the shoulder and wear the outside edge more than your typical r-comp tire. Michelin suggests staying with the stock 33/39 pressure cold because of this. At PSDS they run stock pressure to help out with tire wear with a stock alignment. When you change your alignment to run more camber then you can start to play with tire psi.
People starting out in DE's will normally see around a 5-7psi increase and that depends on there track speeds. I see 10-12psi increases and that depends on teh outside and track temps. As I progressed through the DE ranks my tire temps rose.
Not knowing his alignment specs and tire temps we realy can't say much.
PS2's will roll over on the shoulder and wear the outside edge more than your typical r-comp tire. Michelin suggests staying with the stock 33/39 pressure cold because of this. At PSDS they run stock pressure to help out with tire wear with a stock alignment. When you change your alignment to run more camber then you can start to play with tire psi.
People starting out in DE's will normally see around a 5-7psi increase and that depends on there track speeds. I see 10-12psi increases and that depends on teh outside and track temps. As I progressed through the DE ranks my tire temps rose.
06-17-2010, 04:56 PM
#22
Rennlist Member
Thread Starter
06-17-2010, 05:03 PM
#23
Rennlist Member
Thread Starter
Michelin suggests staying with the stock 33/39 pressure cold because of this. At PSDS they run stock pressure to help out with tire wear with a stock alignment. When you change your alignment to run more camber then you can start to play with tire psi.
People starting out in DE's will normally see around a 5-7psi increase and that depends on there track speeds. I see 10-12psi increases and that depends on teh outside and track temps. As I progressed through the DE ranks my tire temps rose.
People starting out in DE's will normally see around a 5-7psi increase and that depends on there track speeds. I see 10-12psi increases and that depends on teh outside and track temps. As I progressed through the DE ranks my tire temps rose.
I start with 33/39 before I drive to event, and go through first run like that... at the end of the first run (~20mins), I check pressure and drop it (HOT) to 36/42 usually... then I will keep it at around that after each run when tires are hot.
I keep it a bit higher based on my old tracking times, but still lower than max-load recommendation of 37/44, while I've seen it go above that.
06-17-2010, 07:27 PM
#24
Race Director
alexb76, for a beginning DE student start out with 33/39 cold. Do not worry about tire pressure your first few times at a DE. All stated tire pressures in the owners manual are cold tire pressure. If you want to get really techincal they are 68 degree cold tire pressures.
What you are doing now is fine if you want to do that and keep records of your tire pressures.
I use either Toyo RA1 or R888 and they state those pressure in hot terms of 32-38 hot psi. For my cars and driving style and set up I find that 36/37 psi hot works the best. I start out my DW day at 28/29 and bleed from there. When the tires are cold the next moring they are right at 26psi cold. Again this is only for RA1 and R888 which do not roll over the side wall like most street tires with softer side walls.
What you are doing now is fine if you want to do that and keep records of your tire pressures.
I use either Toyo RA1 or R888 and they state those pressure in hot terms of 32-38 hot psi. For my cars and driving style and set up I find that 36/37 psi hot works the best. I start out my DW day at 28/29 and bleed from there. When the tires are cold the next moring they are right at 26psi cold. Again this is only for RA1 and R888 which do not roll over the side wall like most street tires with softer side walls.
06-18-2010, 12:01 AM
#25
Rennlist Member
Thread Starter
Ok, got it thanks. BTW, I tracked Nurubgring with a Suzuki Swift (modded) and R888 tires... OMG did those tires make ALL THE DIFFERENCE!
