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Discussion Starter · #1 ·
Installed a set of Bridgestone RE-11's to replace worn out Continentals on Monday. Haven't had a chance to really push them yet, but after a couple drives up and down the canyon and around, including in the rain, they ride better, are quieter and have more grip--of course this is compared to completely worn out front's and about 65% worn rears, so it's difficult to make a direct comparison. I will be at a DE in two days so that will tell me a lot more. I'll report back then.
Anyone have DE or other experience with their RE-11's?
BW
 

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Several here have AX and/or track experience on RE-11s. I've been using R888s for track and AX, but have completed two AXs on RE-11s this spring. They have very good grip for a street tire; very close to the R888s at AX. A car mag's recommendation to use higher than average tire pressures (they said about 42 psi hot, as I recall), seems correct.
 

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Discussion Starter · #3 ·
Got home a bit ago from my first DE on the tires and all I can is--Wow! These things have a ton of grip. In the first session they got feeling a little greasy, especially the rears, at the end. When I checked the hot air pressure the rears where at 46 lbs (started at 35 cold) and the fronts where 42 lbs (started at 32). I reduced the fronts to 41 and the rears to 42 and that's where the pressure pretty much stayed and they seemed happiest there--no more greasiness the rest of the day. I don't know if that's the best term, but they just seemed to slide around at the higher pressures where they felt planted and grippy at the lower.
They didn't seem to have too much wear at the end of the day--put around 145 miles on them. All-in-all, I'm very happy with the RE-11's.
BW
 

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Good. Another happy RE-11 customer. Your experience on track at 46 psi hot makes sense, but on R-comps that skating feeling starts at lower psi. The 42 psi hot that was said to be the sweet spot for RE-11s was actually for AX, but the track segment they used for testing seemed to me to fall somewhere between a typical AX course and a somewhat small road course.

You might also check the tread-to-sidewall scrub point by seeing how close you came to the tips of the little arrows (triangles, actually) indicating the outside edge of the tread. Just touching the tips of the arrows is supposed to indicate you're using all of the tread width and no more. At AX my fronts scrubbed to the tips at 39 psi hot, but the rears scrubbed to about 1/8" away from the tips at 41 psi. That suggests I might get a better balance by lowering the rears about 2 psi next time. That would mean starting fronts and rears at about the same pressure.
 

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Discussion Starter · #5 ·
Jim,
Thanks, that's great information. I just checked and on the fronts the scrubbing doesn't quite reach the arrows and the rears it goes just barely over the tips. So that would indicate I should have let a little more air out of the fronts and put a few pounds more in the rears?
Thanks,
BW
 

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That's correct. Having both ends rubbing to the arrow tips means you're using all the tread and no more.

But I made an error in suggesting that that alone would produce better balance or more neutral handling (no over-steer or under-steer). It may take a while for me to try to correct myself. If the pressures that produce scrubbing over to the arrow tips at both ends feels good to you, then you're done. But different drivers may like somewhat different handling balances. If I like a little over-steer for the tight turns of autocross, but I'm not comfortable with over-steer on fast sweepers on track, I can adjust tire pressures accordingly.

Going back to the autocross pressures I had above, I incorrectly suggested that I should let out a couple of psi in the rears to get closer to the arrow tips and insure that I was using all the tread. That should provide more grip to the rears, but what if I want a bit of over-steer? In that case, the rears are probably already where I want them, although the scrubbing is not quite reaching the arrow tips.

There's an article on this in the April Roundel (the BMW Club of America magazine) entitled "Analytical Approach" by Brian Aftanas. It's even longer than this post. Brian suggests that, for autocross, you first set the fronts for maximum grip (scrub to the arrow tips), then set the rears so that you get the handling balance you like. For track, I'd probably prefer maximum grip at both ends.
 

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Jim,

What size of 888 are you using? I can't found a suitable size for cayman for 235 and 265 for both 18"&19" wheel.

888 is a very good tyre.

Several here have AX and/or track experience on RE-11s. I've been using R888s for track and AX, but have completed two AXs on RE-11s this spring. They have very good grip for a street tire; very close to the R888s at AX. A car mag's recommendation to use higher than average tire pressures (they said about 42 psi hot, as I recall), seems correct.
 

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I have R888 sizes 245/40/18 and 275/40/18 on the OEM 8 and 9" rims. That size combo is just a few tenths of an inch larger in diameter than OEM at both ends (25.7" and 26.7"), and it retains the OEM front-to-rear diameter stagger. The 275/35/18 size is also available for the rear, with the same 25.7" diameter as the 245/40/18 fronts. That combo might not upset the sensors, and it would lower effective gearing a bit, but it would throw off speedometer and odometer readings more. I also have 9" and 10" forged rims that the 245 and 275 sizes should also work well on.

The R888 sizes for OEM 19" rims aren't a very good fit. The 235/35/19 is okay for the front, but the rear choices are 295/30/19 and 305/30/19. The 295 needs a 10-11" rim width and the 305 needs a 10.5-11.5 rim width. The large increase in tire width between the fronts and rears (235 vs. 295) would probably also adversely affect the handling balance.
 
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