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      09-09-2019, 02:39 PM   #67
rhop101
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Yea think Im just gonna go 225/255 just to play it safe. Mainly using the car on road with maybe 2-3 autocrosses a year at most, so well see what I think about the 255 on the back maybe next time Ill get the 235 if I think its too pushy.

I see what you mean about the flipping. If I was autocrossing more that would definitely be a reason to go with the RE71
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      09-16-2019, 10:15 PM   #68
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Track day at Autobahn CC north

Track day at Autobahn CC north.

Tire temp went up to 190F in front (according to TPMS).
It still held up pretty nicely without being too greasy.





More and more I drive on track, it feels like I may need 18 inch rim.
Tire seems too soft during turn. Maybe too high sidewall from 17 inch 45 series?

Last edited by TajoMan; 09-16-2019 at 10:23 PM..
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      09-17-2019, 07:43 AM   #69
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Quote:
Originally Posted by TajoMan View Post
More and more I drive on track, it feels like I may need 18 inch rim.
Tire seems too soft during turn. Maybe too high sidewall from 17 inch 45 series?
Re-71r have a very soft sidewall. Might be better off with a 40 series if you want a bit more responsiveness out of the tire. What tire pressures were you at? Upping the pressure can help a bit.
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      09-17-2019, 10:09 AM   #70
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Quote:
Originally Posted by bbnks2 View Post
Re-71r have a very soft sidewall. Might be better off with a 40 series if you want a bit more responsiveness out of the tire. What tire pressures were you at? Upping the pressure can help a bit.
Tire pressure was 42/40 hot. (36/33 cold)
It's was higher than I run in Auto X. (37/32 hot)

I thought the RE71r was one of the stiffest tire among 200tw tires.

What other tire has stiffer sidewall? (200tw)
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      09-17-2019, 10:21 AM   #71
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Quote:
Originally Posted by TajoMan View Post
More and more I drive on track, it feels like I may need 18 inch rim.
Still on the 235s? If so, I'd say you've definitely gotten your money's worth out of them!

Regarding your tire temperatures, I haven't seen any published data on recommended tire temps for the RE-71R, but I'd guess that 190 degrees is pretty high. FWIW, I've understood the RE-71R to be more of an autocross tire than a track tire. I've never used them, though.

To run a car with this much weight and power on the track, you'll get a dramatic boost in grip by increasing both your wheel and your tire widths. And by adding some negative camber. And an LSD. And...

Seriously, 8-9" wheels and 245/40s would create a significantly different experience. If cost is an issue, though, I'd start with camber. Just my 2.

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Originally Posted by TajoMan View Post
Tire pressure was 42/40 hot. (36/33 cold)
As I say, I haven't run the tire, but if I had them and didn't know where to start, I'd aim for 35-39 hot.

Perhaps other drivers with track experience on the RE-71R can weigh-in here.
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      09-17-2019, 10:35 AM   #72
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Quote:
Originally Posted by TajoMan View Post
Tire pressure was 42/40 hot. (36/33 cold)
It's was higher than I run in Auto X. (37/32 hot)

I thought the RE71r was one of the stiffest tire among 200tw tires.

What other tire has stiffer sidewall? (200tw)
I know them to have very soft sidewalls in comparison to just about any other 200tw tire. That's one of the reason I think they provide good grip even in the cold. Soft tire compound and soft sidewalls allow a lot of flex. I've seen plenty of picture of RE-71r flexing like crazy under load.

40psi is decently high. I wouldn't go any higher than that. Move to a 40 series tire if you want a sharper response from the tire.
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      09-17-2019, 03:12 PM   #73
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Quote:
Originally Posted by dradernh View Post
Still on the 235s? If so, I'd say you've definitely gotten your money's worth out of them!

Regarding your tire temperatures, I haven't seen any published data on recommended tire temps for the RE-71R, but I'd guess that 190 degrees is pretty high. FWIW, I've understood the RE-71R to be more of an autocross tire than a track tire. I've never used them, though.

To run a car with this much weight and power on the track, you'll get a dramatic boost in grip by increasing both your wheel and your tire widths. And by adding some negative camber. And an LSD. And...

Seriously, 8-9" wheels and 245/40s would create a significantly different experience. If cost is an issue, though, I'd start with camber. Just my 2.


As I say, I haven't run the tire, but if I had them and didn't know where to start, I'd aim for 35-39 hot.

Perhaps other drivers with track experience on the RE-71R can weigh-in here.
The tire lasted pretty good so far.
140 Auto x runs, 3-20 min track sessions. I had to flip it though.

I will be doing 2 more auto x this year and it will be DUN.

Primary focus for me is staying in FS for Auto x. So no wider rim or camber.


Quote:
Originally Posted by bbnks2 View Post
I know them to have very soft sidewalls in comparison to just about any other 200tw tire. That's one of the reason I think they provide good grip even in the cold. Soft tire compound and soft sidewalls allow a lot of flex. I've seen plenty of picture of RE-71r flexing like crazy under load.
That's actually kinda surprising. I thought the RE71r has stiff sidewall.

Maybe going for 235/45/17 was a mistake. 225/45/17 could be better with only 0.1" less thread width.

Next year, I'm thinking about going 245/40/17 on current 7.5" rim.
Apparently, lots of GTI guys run 245 on their 7.5" rim for auto x.
At least I will have shorter sidewall with this setup. (25.4" vs 24.7" in diameter, so 0.35" shorter sidewall. )
Will see how it works.
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      10-15-2019, 09:53 PM   #74
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Cone Halloween

Tires nearing end of it's life.
1 more Auto X left this year.



I really need to work on driving smoothly.


It looks like the tires are squished quite a bit.
Could be better with 18 inch I guess.
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Last edited by TajoMan; 10-16-2019 at 08:16 AM..
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      11-18-2019, 09:34 PM   #75
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last auto x of the year

It was last Auto X of the year.

Due to the weather around here, I had to put on winter tire on 17" rims.
So this Auto X was with stock PSS. (RE71r was pretty much done anyway)



The stock PSS was just so slippery (compared to RE71r)
First couple of runs, car was all over the place.
Weather was fairly cold as well. (40~45F)
Still, I never felt this much sliding with re71r. lol

Weirdly, I kinda think the car felt more balanced (or natural) without too much body roll with PSS.
When I used RE71r, car seems to have excessive body roll on the corner.

Maybe the RE71r is too much tire for the chassis?

Now I have 5 month to think about what tire/size that I want for next year.
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      06-21-2020, 11:14 AM   #76
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First Track Sprint this year.



I ended up with 225/45/17 Hankook RS4.
It has stiffer sidewall than RE71r for sure. Surprisingly quieter as well.
Ultimate grip level seems little less than RE71 but I feel like this tire is batter suited for the stock suspension. (Maybe RE71 was little too much?)

Haven't tried it for auto x yet. Will see how the shoulder wears.
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      06-24-2020, 08:08 PM   #77
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Quote:
Originally Posted by TajoMan View Post
I ended up with 225/45/17 Hankook RS4.
It has stiffer sidewall than RE71r for sure. Surprisingly quieter as well.

Haven't tried it for auto x yet. Will see how the shoulder wears.
This is the tire I use for track and auto-cross. Seriously, it's quieter than the RE71? Oy. I guess my PSS really have me spoiled for a quiet tire, because I hate how loud the RS4 is. Can't wait to get them off the car after a track weekend.

Yes, the RS4 has very stiff sidewalls. Totally unlike the PSS. Virutally no roll-over scrubbing. Even running at 32-34 PSI hot (starting about 25 PSI cold), I've just barely gotten to the the little triangle edge markers. And when I did, I reversed them to start wearing on the other side.

You'll probably find that the RE71 was better at auto-x. It sticks better when cold. But if you're just doing it for fun, the RS4 is plenty capable.

Do watch your pressures though. If you get over 36-38 PSI hot, the RS4 will start sliding like crazy.
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      06-24-2020, 08:33 PM   #78
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Quote:
Originally Posted by ggggbmw View Post
This is the tire I use for track and auto-cross. Seriously, it's quieter than the RE71? Oy. I guess my PSS really have me spoiled for a quiet tire, because I hate how loud the RS4 is. Can't wait to get them off the car after a track weekend.

Yes, the RS4 has very stiff sidewalls. Totally unlike the PSS. Virutally no roll-over scrubbing. Even running at 32-34 PSI hot (starting about 25 PSI cold), I've just barely gotten to the the little triangle edge markers. And when I did, I reversed them to start wearing on the other side.

You'll probably find that the RE71 was better at auto-x. It sticks better when cold. But if you're just doing it for fun, the RS4 is plenty capable.

Do watch your pressures though. If you get over 36-38 PSI hot, the RS4 will start sliding like crazy.
I was surprised as well. RS4 is definitely quieter (at least when new) than RE71r.
Compared to those 2 tires, PSS is like marshmallow. So soft and quiet.

Thanks for the tip. I will watch the pressure.
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      06-24-2020, 10:02 PM   #79
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Quote:
Originally Posted by ggggbmw View Post
I've just barely gotten to the the little triangle edge markers. And when I did, I reversed them to start wearing on the other side.
This may not be relevant here, but the purpose of the triangles on a sidewall is to indicate where in the tread the tires' wear bars are located. Alternatives to the triangle are the manufacturer's logo (used by Michelin) and the text string 'TWI'.

I mention it because many drivers think the triangle indicates how far they should be or could be exercising a tire's tread.
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      06-25-2020, 03:16 PM   #80
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They do provide a very graphic display of how badly the street tires keel over on track though. I think mine were gone after the first weekend.
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      06-25-2020, 05:37 PM   #81
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They do provide a very graphic display of how badly the street tires keel over on track though. I think mine were gone after the first weekend.
haha. yes
Mine on RE71r were gone after 1 auto x school with 26 runs on concrete.
Also auto x ed with MPSS couple of times and letters on the side wall were worn.

While that triangle is not a proper "using all the tread" indicator, it certainly shows how badly the tires roll. lol
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      06-26-2020, 09:37 AM   #82
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Originally Posted by TajoMan View Post
The tire lasted pretty good so far.
140 Auto x runs, 3-20 min track sessions. I had to flip it though.

I will be doing 2 more auto x this year and it will be DUN.
I'm shocked you were able to get so much life out of your tires! I only got about 75 runs out of my first set of 245/40/17 RE71R, and that was with flipping the tires and no track/open lapping sessions. And they were pretty much down to the cords at that point. Maybe it comes down to a difference in track surfaces to some degree.
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      06-26-2020, 04:34 PM   #83
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Originally Posted by nubbster927 View Post
I'm shocked you were able to get so much life out of your tires! I only got about 75 runs out of my first set of 245/40/17 RE71R, and that was with flipping the tires and no track/open lapping sessions. And they were pretty much down to the cords at that point. Maybe it comes down to a difference in track surfaces to some degree.
Mine was done after around 160 runs or so.
At least half of those were on very grippy (rough) concrete surface.

You do need to spray water. Overheating will kill re71r badly.
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      06-27-2020, 07:51 PM   #84
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Quote:
Originally Posted by dradernh View Post
This may not be relevant here, but the purpose of the triangles on a sidewall is to indicate where in the tread the tires' wear bars are located. Alternatives to the triangle are the manufacturer's logo (used by Michelin) and the text string 'TWI'.

I mention it because many drivers think the triangle indicates how far they should be or could be exercising a tire's tread.
aerobod once again, you are a font of incredible knowledge. I little googling confirms you are right on this. But, as a side benefit, they do seem to work pretty well as tire rollover indicators also. I've found that on a performance tire, if you are scrubbing them off, you are probably abusing the tire or the pressures are wrong.

I do love the little smiling Michelin Bibendum triangles. Always enjoy when a manufacturer has a little fun with something like that.
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