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Old Dec 1, 2015 | 04:21 PM
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Default Front wheels jump

Hi all!
Has anyone felt a pulsating or jumping of the front wheels when turning sharp (almost to stop) when going very slow. Like backing out of parking place. Seems more pronounced when cold. Almost feels like tires are trying to grip. My 997 did this but was a 4S and since the front tires had drive, it was normal. Did a search but didn't come up with anything. TIA as always.
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Old Dec 1, 2015 | 04:22 PM
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Ackerman effect. Been discussed many, many times. Normal.
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Old Dec 1, 2015 | 04:30 PM
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I am familiar with the effect, but does anyone know what exactly causes it? Also, why is there not a fix for it? It's extremely annoying.
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Old Dec 1, 2015 | 04:45 PM
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Lex "Acorn" Van will chime in ...
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Old Dec 1, 2015 | 04:47 PM
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https://rennlist.com/forums/991/8003...e-problem.html
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Old Dec 1, 2015 | 05:00 PM
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Originally Posted by drcollie
Ackerman effect. Been discussed many, many times. Normal.
^^^ +1 WAY TOO MANY TIMES. Wonder if the op doesn't know about the search feature?
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Old Dec 1, 2015 | 05:19 PM
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Every time this happens, I know it's coming, and it still scares the crap out of me. I either think I have a slashed tire or the wheel fell off.
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Old Dec 1, 2015 | 05:21 PM
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I did search it......sorry if I didn't know the exact "effect"
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Old Dec 1, 2015 | 05:24 PM
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Thanks happy.....appreciate the link and to others that helped. Sure didn't want to bother you homeless!
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Old Dec 1, 2015 | 05:26 PM
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FWIW, on my Boxster this effect more or less vanished when I switched from PZero to MPSS tires. Something to think about when it's time for new rubber.
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Old Dec 1, 2015 | 06:03 PM
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Want to fix the Ackerman effect? Easy, put little skinny tires on the car and it won't do it.

Here's a video on it - try to stay awake when you watch....lol

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Old Dec 1, 2015 | 06:04 PM
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Originally Posted by GraSox
Thanks happy.....appreciate the link and to others that helped. Sure didn't want to bother you homeless!
Didn't bother me. It's a yearly thing at this time of the year this question comes up. Keep watching, someone else will ask the same question.
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Old Dec 1, 2015 | 06:07 PM
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Originally Posted by drcollie
Want to fix the Ackerman effect? Easy, put little skinny tires on the car and it won't do it.

Here's a video on it - try to stay awake when you watch....lol



Dr. C you need a haircut!
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Old Dec 2, 2015 | 10:31 AM
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Originally Posted by Homeles
^^^ +1 WAY TOO MANY TIMES. Wonder if the op doesn't know about the search feature?
The search feature on this site is actually pretty bad compared to every other forum i've ever used.
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Old Dec 2, 2015 | 11:16 AM
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Yes, the search feature is poor. Have searched several times and unless you know the exact phrase or "effect" you won't get a hit.
Thanks again to all who helped me, as usual most are great.
Homeless, be a little more patient with people. This is a great site with very knowledgeable people willing to help others. A simple " try acorn effect " as others did would have been great, not saying I don't know about the search function. If you would have read my initial post, I did search. Just saying..........
Thanks again guys!
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