my RA1s seemed to be losing a little grip at roebling after a few laps. I initially thought it was tire pressure, but after further investigation i believe the tires were graining. the rubber started to roll up on the sides of the tread pattern.

what causes this?

 

hows your alignment?

 

Were you running them full-tread or shaved?

 

are you sure it just wasn't 'pick up' from the cool down lap?


Also if you push a tire past its grip level, and keep doing it, the tire is going to fall off.

 

I actually had a ton of graining on my toyo's at the nationals. I am still trying to track down what exactly caused it.

 

I find that proper heat cycling of Toyo's are critical to consistent grip

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FlyZlow &raquo;</TD></TR><TR><TD CLASS="quote">Were you running them full-tread or shaved?</TD></TR></TABLE>

yeah that was the problem just realized a little bit ago.

 

it is happening on my full tread 225/45/15, and a couple other friend's full tread tires as well. They are starting to get better as the tread wears away though.

I did about 35 miles on them before I got them on the track. I then did the first session pretty easy and then tried harder the next and got them pretty hot, probably too hot.

Yesterday they could have fallen off after about 28 minutes of hard tracking, not sure, but the tire pressures did not raise abnormally though.. . We'll C how the next session goes, I hope they get better.

After 1st day:
the ones furthest away are the ones I used on the front. 4 heat cycles

Here the ones nearest are the fronts, pics at the same time.


2nd day: Pretty it was a wet track for the first few sessions and then heated up to maybe 70deg track temps towards the end. 30-40mph winds!!
The ones furthest away are the fronts again. I rotated the rears to the front for this day. 7 heat cycles later

 

What the heck is "graining" ? Those tires look just fine...

 

&lt;--- Wondering the same thing... Do they mean chunking or something? Doesn't look like it though.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ &raquo;</TD></TR><TR><TD CLASS="quote">What the heck is "graining" ? Those tires look just fine... </TD></TR></TABLE>

graining is when the rubber of the tire rolls up on the sides of the tread.


about the tire pressures, they were a little funky for me. I put 35 in the front when they were cold, and when I got off track, after going through the cool down lap and throuhg the pit lane and parking back at my spot, they were back at 35 psi.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote"></TD></TR></TABLE>

there is a good example of the graining. see the tire on the right side, and the tread on the right side of that tire, how it is raised at the edge of the tread?

 

I've been going to the track for a long time... never heard that word. Sounds like something the riceboiz made up?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drewbie &raquo;</TD></TR><TR><TD CLASS="quote">the tread on the right side of that tire, how it is raised at the edge of the tread?</TD></TR></TABLE>

Still dont see a problem with your tires.

If your pressures coming off the track are the same as when you went out, you're not driving too hard.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ &raquo;</TD></TR><TR><TD CLASS="quote">I've been going to the track for a long time... never heard that word. Sounds like something the riceboiz made up?

Still dont see a problem with your tires.

If your pressures coming off the track are the same as when you went out, you're not driving too hard.</TD></TR></TABLE>

graining? do you watch f1?

 

thats what I was always told it was. not saying you do not know what you are talking about.

my tires had the same thing happen to them, the rubber rolling up like the pic above.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drewbie &raquo;</TD></TR><TR><TD CLASS="quote">

graining? do you watch f1?</TD></TR></TABLE>

Every time I try, I fall asleep.

The tires are fine Dont worry, go drive

 

I'm not saying I see or experience a problem with my tires. I'm just trying to help this guy out and point out what it looks like and say it is basically typical.

Full tread RA1s do it . Its like the rubber just peals away. I think it is a non issue most of the time when the RA1s are shaved and/or are worn past the tire tread pattern. At least I hope so. This is my first set of R comps.

Graining = "Feathering" to others as well.. . Graining doesn't really seem like the correct term to me but I knew what you meant DREWBIE.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drewbie &raquo;</TD></TR><TR><TD CLASS="quote">

graining is when the rubber of the tire rolls up on the sides of the tread.

about the tire pressures, they were a little funky for me. I put 35 in the front when they were cold, and when I got off track, after going through the cool down lap and throuhg the pit lane and parking back at my spot, they were back at 35 psi.

there is a good example of the graining. see the tire on the right side, and the tread on the right side of that tire, how it is raised at the edge of the tread?</TD></TR></TABLE>

Try not to take such easy cool down laps if traffic will allow. Don't blitz down the straights but try to enter the corners at about what you normally do. This will help keep the tire pressures up if you do not hot pit and check them from time to time. After a cool down lap like this, you should only see around 1-2 PSI drop.

If I start my fronts at 35 PSI, I will for sure get them around 43PSI or higher depending on how hot the track is and how much I overdrive the car.

You want your fronts to be b/t 35-38 hot. Lighter the car, the less air pressure you can get away with.

I like to see 36-37PSI when I pit in after one cool down lap.

I think the edges roll up b/c that is where the rubber is the hottest at times and it collects rubber and fuses together

 

Tires need more heat, camber & pressure. As a general rule, those tires should be around 38-40 psi hot coming off track even with a cool down lap. Wear looks too even across the face to be getting max grip thru corners. Add more negative camber.

I have experienced the feathering effect even with correct tire temps & hot pressures if there wasn't sufficient negative camber.

Yes, full tread RA-1 are more prone to this effect/condition than shavers. We only run full depth for RA-1s for rains.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 6spdKEG &raquo;</TD></TR><TR><TD CLASS="quote">

Try not to take such easy cool down laps if traffic will allow. Don't blitz down the straights but try to enter the corners at about what you normally do. </TD></TR></TABLE>

Just don't do this and come flying up on someone's ***. They won't like it.

&lt;--- Had to almost move out of the way of a particular blue E46 M3 doing this....
"But it was a test and tune, I need to get hot tire pressures!" Well then pit in a lap early, dumbass, rather than wreck on the ******* cool down! Sorry, not directed at anyone here, just a little bitter

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by civicrr &raquo;</TD></TR><TR><TD CLASS="quote">Tires need more heat, camber & pressure. As a general rule, those tires should be around 38-40 psi hot coming off track even with a cool down lap. Wear looks too even across the face to be getting max grip thru corners. Add more negative camber. </TD></TR></TABLE>

Thanks for the tips. I run 2.6-2.7 front and rear as of now. Very slight toe out in front, Zero toe rear.

So there should be more inside wear??

Looking back at some stats, I actually see 37.5-39 hot coming off the track after one cool down lap. I heard the sweet spot for my weight of car (2480 with driver) is about 38PSI.

I'm running about 37PSI rear to help with my understeer problem and could probably add a few pounds as well.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Stinkycheezmonky &raquo;</TD></TR><TR><TD CLASS="quote">

Just don't do this and come flying up on someone's ***. They won't like it.

&lt;--- Had to almost move out of the way of a particular blue E46 M3 doing this....
"But it was a test and tune, I need to get hot tire pressures!" Well then pit in a lap early, dumbass, rather than wreck on the ******* cool down! Sorry, not directed at anyone here, just a little bitter </TD></TR></TABLE>

nope, I don't fly up people's rear ends. The last few track days I've been in lately I just get off the track when I want but when I do get the checker, I'm pretty nice out there b/c usually I have been the one having people fly up on my ***. When the track is still hot, lolly gaggin around on the cool down on open track days concerns me. I find it better to carry the corner speed a bit off line so when the time comes and that someone has caught up on the straight and is actually behind you in the turn, you aren't a road block out there causing them to take extreme measures to avoid you in the corner. It's not like you can stop and wait for them out there so if they mess up, that sucks, but I've already done my best to get out of the way.

 

That's interesting. I always take it pretty easy on the cooldown lap, being that it's, y'know, a COOLDOWN lap. My car does get hot, and I know for sure that coming in with everything hot and just parking it is bad news. If the douche behind me screws up his tire pressures a little because of that, too damn bad. There's no good reason for a person to wait for the slowest lap of the session to do that, seriously. I'm saying this from an HPDE standpoint, keep in mind, and I'm not picking on you or anything. Just commenting on other's behaviors.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 6spdKEG &raquo;</TD></TR><TR><TD CLASS="quote">

Thanks for the tips. I run 2.6-2.7 front and rear as of now. Very slight toe out in front, Zero toe rear.

So there should be more inside wear??

Looking back at some stats, I actually see 37.5-39 hot coming off the track after one cool down lap. I heard the sweet spot for my weight of car (2480 with driver) is about 38PSI.

I'm running about 37PSI rear to help with my understeer problem and could probably add a few pounds as well.

nope, I don't fly up people's rear ends. The last few track days I've been in lately I just get off the track when I want but when I do get the checker, I'm pretty nice out there b/c usually I have been the one having people fly up on my ***. When the track is still hot, lolly gaggin around on the cool down on open track days concerns me. I find it better to carry the corner speed a bit off line so when the time comes and that someone has caught up on the straight and is actually behind you in the turn, you aren't a road block out there causing them to take extreme measures to avoid you in the corner. It's not like you can stop and wait for them out there so if they mess up, that sucks, but I've already done my best to get out of the way. </TD></TR></TABLE>

you run toe out in front and no toe in rear? seems odd to me.

your car will turn better with toe out in rear. why do you have toe out in the front? im just curious; i have not heard of anyone doing this before.

 

okay, last words about the "cooldown lap" If the darn course is HOT and I'm cooling down.. . I'm mainly cooling down my brakes but I'm never runnin hot engine temps or too hot of oil temps. I'm not going into corners at high RPMS and usually not in the same gear I normally take the turn in.. .

if i was in HPDE, yeah, I'd probably not be able to take the corners so fast b/c of traffic but mainly I've been on hot tracks coming in and on whenever and without and instructor telling me to slow down.. . And if I did have an instructor be like "what the hell are you doing" I'd just tell him I want to get some good tire pressures and work on being smooth lol!

I know you are an instructor stinky, but do you really see HPDE students rollin into the pits to take a hot pit for pressures and temps?

The OP is going out with 35 and coming in at 35, something is up here.. .

I'm not sure when the OP is getting track time but I guess the advice here is either
1.) just hot pit.. . hopefully you have a friend to help out
2.) if you don't and you can still go slow on straights and fast in corners without using the brakes, you should be fine figuring that your tire pressures are probably 1-2 PSI lower after one mildly aggressive cool down lap.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 6spdKEG &raquo;</TD></TR><TR><TD CLASS="quote">okay, last words about the "cooldown lap" If the darn course is HOT and I'm cooling down.. . I'm mainly cooling down my brakes but I'm never runnin hot engine temps or too hot of oil temps. I'm not going into corners at high RPMS and usually not in the same gear I normally take the turn in.. .

if i was in HPDE, yeah, I'd probably not be able to take the corners so fast b/c of traffic but mainly I've been on hot tracks coming in and on whenever and without and instructor telling me to slow down.. . And if I did have an instructor be like "what the hell are you doing" I'd just tell him I want to get some good tire pressures and work on being smooth lol!

I know you are an instructor stinky, but do you really see HPDE students rollin into the pits to take a hot pit for pressures and temps?

The OP is going out with 35 and coming in at 35, something is up here.. .

I'm not sure when the OP is getting track time but I guess the advice here is either
1.) just hot pit.. . hopefully you have a friend to help out
2.) if you don't and you can still go slow on straights and fast in corners without using the brakes, you should be fine figuring that your tire pressures are probably 1-2 PSI lower after one mildly aggressive cool down lap. </TD></TR></TABLE>

i was at Roebling, so the brakes wernt really an issue. it was also my first time on r compounds. the grip was rediculous. i did not find their limit that day.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drewbie &raquo;</TD></TR><TR><TD CLASS="quote">

you run toe out in front and no toe in rear? seems odd to me.

your car will turn better with toe out in rear. why do you have toe out in the front? im just curious; i have not heard of anyone doing this before.</TD></TR></TABLE>

Many people run toe out in front mainly b/c the effect of braking forces making the car toe in. I actually tell the alignment guys to get it near zero with barely any toe out and that toe in is not favorable.

Zero toe rear b/c well, I was told to start there from couple racers that prefer that. I do drive this car on the street as well.. . and yes, I'm aware that toe out will allow the rear to come around a bit better.