Squirrely Handling After New Tires
 

I just had a new set of Yokohama Avid V4S installed on my '86 911. As part of Mr. Tire's package, they provide a free alignment check, which showed that the steering rack was pulling to the right (I should have gotten the numbers but did not). In any event, the front end was aligned (fortunately, the rear was within spec). After much effort on the tech's part, he was able to adjust the tie rods...I should have been more inquisitive as to his experience with 911s):rolleyes: In any event, the tires feel good and whatever shimmy I had at speed with the old tires is gone. The problem I think I have now is that the steering is somewhat vague. It's as if a sudden change in direction induces more roll than movement in the direction that I steer. Could a poorly done alignment cause the problem, or, could worn tires have masked the problem, or, or could something else be going on here?

I lifted the front end and noticed a little play with the left front wheel when I grabbed it at the top and the bottom. he right wheel is solid. Also, when I turned the wheels lock to lock, I could hear a noise coming from the smuggler's box, although it did not appear as though anything was binding.

The car is used just for street driving. I am running 36 psi in the rear and 32 psi in the front. Tire sizes are 205/55-16 & 225/50-16.

Thanks as always.

Mike

tire shop alignment :( . oh boy! do the tires have stiff sidewalls? push the car sideways repetedly, at the bumpers, and see if the sidewalls move much.

Don't forget about the breakin period for the tires.

When I first put rear tires on my car...I was shocked at amount of "squirrel"...thought something was MAJOR wrong. Within several hundred miles, they gripped like all hell. Of course, I didn't dare let this shop touch my alignment, as there were no alignment issues.

Not sure if this is what you're sensing or not. I stick with the door displayed pressures of 36/R and 29/Front.

The play in the wheel sounds like bearing issues (?)

Best,


Best,

I'll lower the pressure on the front and see how that feels. I did the push on the bumpers as suggested and do appear to have fairly flexy side walls. :( I have 500 miles to return them; I will see if either I or the tires adjust before then.:confused:

Thanks again for your help.

Mike

I have the V4S tires on my SC, I've not experienced any odd behavior, for normally driving I run at the recommended pressure, for autocross I've gone up to 34F and 37R and they still drive great.

Jay

Get the alignment checked or check it yourself.

Can be a bad ball joint. Also check if the wheel is tightened.

A couple of the nuts on the left front were definitely not as tight as as they should have been (I didn't have the torque wrench on it, although the amount of effort required was no where close to 90-95 foot pounds:mad:). All nuts have been re-torqued. Tomorrow's test drive should tell the story.

Thanks again.

Mike

For what it's worth, the pulling issue is more likely a result of uneven caster than incorrect toe. Hopefully he checked that as well. Adjusting the tie rods has nothing to do with that. There should also be no play at all, as you describe. Was there any play after you torqued the wheel nuts? An incorrect toe setting can make the car feel like it isn't very eager to turn into a corner. Porsche specifies the toe setting "pressed" which means they want you to set it after you install a device between the front tires that pushes on them with a cretain amount of force. Did he do this?

JR

Can you post the numbers that you ended up with after the alignment?

You might want to try a different set of tires. I had the same problem with my 74'. I got new tires. It went from nice accurate steering to what seemed like a flat rear tire. Felt like the rear end wanted to come around with the slightest turn. Too soft side walls sounds like your problem.

If tires is the only change you've made from OK to NOT OK, I'd change to a different tire. Tell your tire guy, "these don't work."

My $0.02
Paul

Did you do what this guy did? http://tinyurl.com/5uh2nn

He put Armor All on his tires to make them "jet fockin' black." Unfortunately, he Armor Alled the tread, to. Talk about squirrelly! (The Armor All guy is one of my all-time favorite threads). Sorry to hijack!

The YOKOs in particular seem to have a lot of mould release still on them when new. It wears off after a few hundred miles of so. I wouldn't mess with tire pressures or alignment until you're sure that's not the problem.

That's been my experience with the last 2 sets of YOKOs that I've put on my car (my mech. warned me about this when I put the first set on).

Are those all weathers? If so switch to summer tires (if it is not a daily driver).

I tried some Bridgestone 960 AS Pole Positions and they were TERRIBLE..
I swapped them to Goodyear F1 DS-GS summer tires and they are really great.
I went from slipping all over the place to an awesome handling Pcar with great grip.

The alignment needs to be done by someone that understands 911s. Local shops usually have no clue and cannot dial you in.

Are those all weathers? If so switch to summer tires (if it is not a daily driver).

I tried some Bridgestone 960 AS Pole Positions and they were TERRIBLE..
I swapped them to Goodyear F1 DS-GS summer tires and they are really great.
I went from slipping all over the place to an awesome handling Pcar with great grip.

The alignment needs to be done by someone that understands 911s. Local shops usually have no clue and cannot dial you in.

I stopped back at the shop this morning and was given the readings before the alignment was done last week which were: Camber: -0.2 degrees (left) and -0.6 (right); toe: 3.93 degrees (left) and -3.63 degrees (right). They did not have the readings from when after the alignment was done, in which case, they put the car back on the rack and took readings which were way out of spec (I was told the car was in spec last week after the alignment). In any event, the readings after today's alignment are now: camber: -0.6 (left and right); caster adjust: 6.0 degrees (left) and 5.0 degrees (right) and toe: 0.13 degrees (left and right).

BIG lesson learned here: find a shop with a tech that worked on a 911-the tech while he was careful and courteous (despite his reference to my car as a museum piece):eek: had some real problems trying to adjust the tie rods, so much so that I was asked to leave the service bay since I might be making him nervous. :rolleyes: The upside is that I have a few hundred miles within which to decide to either keep or pitch the tires. Also, I can go to any Mr. Tire to have the work done. The Porsche mechanic I go to for mechanical work recommended a Mr. Tire closer to him...I should have taken it there although I thought it was too inconvenient, that was BEFORE I spent 2 hours at Mr. Tire last week and another 2 hours today!!!:(

I drive 60 miles from home to Gardena, CA to get a good alignment.

When buying my last set of tires, I had my thinking about old 911 alignment realigned :).

Noticing the wear pattern on my YOKO AVS ES100 tires (worn into the wear bars, slightly more toward the inboard sides, at about 18k miles), and before buying new tires, I took it to my mech.'s alignment guy who's very experienced aligning 911s (for street and track).

He asked me if I was unhappy with the mileage I'd gotten out of the tires, which I wasn't. Then he asked me if I was unhappy with the handling, which I wasn't.

Then he asked me what I wanted him to do. I said,"Huh?". Do you want a more agressive camber for looks or for the track?, he asked. Uh, no, I answered, to which he replied that I didn't really need him to do anything.

He said he's had a number of 911 owners want increased camber for the look, didn't track their cars and then were shocked at their tire wear, so for years he's "interviewed" his customers as he did me.

I thanked him (there was no charge) and drove off with a smile on my face and my money still in my wallet. Honesty rules! :D

They had before readings but no after readings? If so, that seems odd unless they never did/finished the alignment and rolled your car out to get the next one in. This is a good lesson for sure. It makes sense to avoid the tire shops where there's a premium on business volume and the skill/quality of the tech might not be all you'd hope for.

I have the Godyears and can't stand them, really. To me, they seem very squirrely or "sqoogey" as I call it. Sidewalls seem too soft, and I get nothing but tire squeal at Autocross.