JohnPG

I'm getting tired of the Hoosiers going out of round or balance. Whatever the cause after a couple of sessions they get pretty rough to drive. Additionally they seem to be losing grip after fewer heat cycles this year than last. In any case I'd love some feedback from folks who've used both and what sizes you use and how the Kumho performs relative to the R6. Currently I've been running 245/40 f and 315/30 rears, they seem to work well as far as ABS is concerned, though I haven't tried different sizes since I went to steel rotors.

TIA

Cheers John

996FLT6

If the tires rotate over the wheel which seems to happen with grippier tires u will have steering wheel vibration ie car feels out of balance. Kuhmos will rotate too. Kuhmo v710's sizes are 245/40 square 305/30 square. They will last much longer then Hoosiers. Hot pressures not above 32 psi for kuhmos. Mike

ukrbmw

Yep, I get some serious vibration out of my Hoosiers, but boy - they still stick like glue! Don't get overly upset about them, tires are good just very freaking sticky!

Boinkus44

I also had a serious problem with rotating Hoosiers (multiple sets) and it drove me crazy. I switched from Fikse polished wheels to Forgelines (slightly rougher finish) and problem almost completely eliminated. So far, 2 sets of Hoosiers on the Forgelines and minimal to zero rotation. YMMV

I do like the sound of more heat cycles out of the Kuhmos though, but they always seem out of stock - at least in Ontario so I haven't yet tried them.

SH || NC

The polished finish where the bead sets really made that much of a difference? Seems like such a small surface area. Could they have been installed with some kind of adhesive on the Forgelines perhaps?

LVDell

There really isn't a good wheel that can keep a tire from rotating when you are braking with 6-pots and race pads when you are really hard on the binders at high speed.

Make sure the tires do NOT get mounted with and lube. I also use the "aquanet" trick and it works. Never had a tire rotate on a wheel.

JohnPG

Perhaps it is just the rotation issue. I think it may be more, I've remounted and rebalanced in the past and was right back to heavy vibrations after one session. A friend of mine with a 996 turbo got fed up and tried Goodrich R1's and claims they don't have this issue. Can't say if they have rotated as well. He seems to think the R6 go out of round after 3-4 sessions. Some vibration is fine, but sometimes seeing double vision is too much excitement.

John

Boinkus44

I have to admit that I was a little skeptical, but I tried everything with the Fikses - aquanet, dry mount and variations thereof, and the tire rotation was hugely problematic. Like having to significantly back off on the straights at Mosport and the Glen because the vibaration was almost violent. I also marked the tires and they would continue to move every session. The fronts under braking and the rears under torque. With the Forgelines, no aquanet, and a low lub tire mount, I haven't had 2" of rotation and virtually no vibration. I'm happy....Still interested in the Kuhmos though.

JohnPG

Violent is the word going into the bus stop at the glen. Going to be there for five days beginning the 24th so I need some tires. I'll try the dry mount (not going there) and the aquanet. My wheels are CCW with a bead blasted finish so they are a bit rough.

Steve, it was good meeting you at CMP. Too bad we didn't get to run together at LMT.

John

JeremyS

Another vote for tire rotation relative to the wheel. My sports racer generates over 3G under braking and had this problem with both GY and Hoosier slicks. Lightly sandblasting the bead seats of the wheels completely eliminated the rotation. I am now able to use mounting paste and still get no slippage.

Boinkus44

That was good fun at CMP but it ended early for me with a tank of bad gas. At LCMT I got put in the Orange group so we didn't see the track together. I'm actually at the Glen for 3 days starting the 29th so I'll just miss you, but looking forward to driving there with Hoosiers AND wheel balance. Hopefully you can get the rotation issue under control. Doesn't hurt to let the wheels sit for a few days after tire mounting before driving. Every little bit helps.

Hope to catch up with you again. Love those black 6GT3's...

Cheers,

Steve

mtesh73

plus one on the "hair spray" technique. works wonders for motorcycle grips as well.

JohnPG

Mike,

Hot pressure at 32, do you normally see a 8-10 psi gain from cold?

J

996FLT6

I run 25-26 cold with kuhmos. Usually goes up to 33-34 rear and 31-32 front and I like it 31 hot all around on kuhmos. Mike

Boinkus44

Not sure if it is a tire issue, ambient temp issue or a set-up issue or a combination of all of the above, but I get a cold-hot pressure rise of about 10 lbs on the front and 14-16lbs on the rears with Hoosiers. Seems like the Kuhmos top out earlier. Curious if your Hoosiers increased in pressure a similar amount as the Kuhmos seem to do. Thanks.