Grrr wet understear

Associate
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well thats cheap chinese tyres for you! i work at a car garage and we have countless people comming in saying they got new tyres but there cars slide all over the place (someone in a new VW passat) its always chinese tyres! no matter hot much tread they have, there rubbish. get some good italian tyres or similar. dont buy chinese, indonesian or tiwaneese tyres xD we usually are always requested to replace there brand new tyres as sometimes there that bad they say there cars are undriveable! marangonnoi is a really good tyre to fit to ur bmw xD we have a set on out bmw 540i 4.4 v8. they grip like mad!
 
Caporegime
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well thats cheap chinese tyres for you! i work at a car garage and we have countless people comming in saying they got new tyres but there cars slide all over the place (someone in a new VW passat) its always chinese tyres! no matter hot much tread they have, there rubbish. get some good italian tyres or similar. dont buy chinese, indonesian or tiwaneese tyres xD we usually are always requested to replace there brand new tyres as sometimes there that bad they say there cars are undriveable! marangonnoi is a really good tyre to fit to ur bmw xD we have a set on out bmw 540i 4.4 v8. they grip like mad!

marangonnoi? It's Marangoni... but they are still crap.
 
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How do you understeer at 10mph? :confused:

I've done it before :( wet roundabout with negative camber. Fortunately no one in the outside lane and I could take an earlier exit than intended..

so? crap tyres are crap regardless of tread :confused:

Yes and no. Different tyres deal with wet roads differently.. obviously. But one set of tyres might have good dry performance but rubbish wet performance, while another set could have mediocre dry and mediocre wet performance - it's not as simple as saying 'these tyres are crap in the wet therefore they're crap' - as they may be very good in dry :)
 
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I've done it before :( wet roundabout with negative camber. Fortunately no one in the outside lane and I could take an earlier exit than intended..



Yes and no. Different tyres deal with wet roads differently.. obviously. But one set of tyres might have good dry performance but rubbish wet performance, while another set could have mediocre dry and mediocre wet performance - it's not as simple as saying 'these tyres are crap in the wet therefore they're crap' - as they may be very good in dry :)

Well it is as simple as that, if the tyres are dangerous in the wet, they are indeed crap tyres full stop. Unless they are slicks or cut slicks for a trackday.
 

mjt

mjt

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Yes and no. Different tyres deal with wet roads differently.. obviously. But one set of tyres might have good dry performance but rubbish wet performance, while another set could have mediocre dry and mediocre wet performance - it's not as simple as saying 'these tyres are crap in the wet therefore they're crap' - as they may be very good in dry :)

there are some 'big' brand tyres out there that are appalling in the wet, but actually quite reasonable in the dry.
they're still not really very good though are they, seeing as precipitation is quite a common phenomenon..

the op's tyres, however, are just crap full stop. the name is the giveaway ;)
 
Soldato
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my brother had a 1.2 clio a while back and it came with seriously bad no brand tyres. no joke, you coudl exit a roundabout in second, put your foot down and the weedy little car would wheelspin all the way down the road

just imagine trying to stop the thing?!
 
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my brother had a 1.2 clio a while back and it came with seriously bad no brand tyres. no joke, you coudl exit a roundabout in second, put your foot down and the weedy little car would wheelspin all the way down the road

just imagine trying to stop the thing?!

NO ITS OK AS THEY MEET SAFETY STANDARDS AND WOULDN'T BE ALLOWED TO BE SOLD IF THEY WERE DANGEROUS LOLOLOL
 
Soldato
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too right. they were above the legal tread requirement, that was because they were made of bakelite and were never ever going to wear
 
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Only when a vehicle has king pins, which means some old classics and goods vehicles mainly. I can't think of any modern cars with king pins, therefore it's steering axis inclination ;)

No, both are correct terms, KPI still refers to the theoretical position of the "virtual" kingpin, just that KPI is the term used in Motorsport and has become the term generally used to describe Steering Axis Inclination.

steering_axis.gif
 
Soldato
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ALL cars do this to some extent, it's caused by a combination of the castor angle and the "steering axis inclination" (SAI). Camber also changes with body roll to some extent (unless you have a live axle).

Its actually more complicated than that, and depends on whether you are running double wishbone or struts. If you are running double wishbone and the inboard mounts make the geometry a virtual parallelogram, then camber change will be minimal.

More usually the upper wishbone will be shorter, and its inner mount further out than the lower wishbone, this gives increasing negative camber as the suspension compresses. this is good for maintaining a square contact patch during cornering, however the steering rack geometry can cause high amounts of bump steer and toe change during acceleration and braking.

A strut will keep the suspension more consistent in terms of camber change as the movement is more linear regardless of the SAI/KPI. Due to this, you will often see strut based cars running more static negative camber than cars with wishbones (if used on the track).

There is a good simulator for WISHBONES showing how different length wishbones, mounting points etc affect camber change here http://www.racingaspirations.com/?p=286

Have a play with it, make it parallel, move the upper left point left and right and see how the camber changes, change the spacing of the steering pivots (SAL) see how that changes the camber change.
 
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well thats cheap chinese tyres for you! i work at a car garage and we have countless people comming in saying they got new tyres but there cars slide all over the place (someone in a new VW passat) its always chinese tyres! no matter hot much tread they have, there rubbish. get some good italian tyres or similar. dont buy chinese, indonesian or tiwaneese tyres xD we usually are always requested to replace there brand new tyres as sometimes there that bad they say there cars are undriveable! marangonnoi is a really good tyre to fit to ur bmw xD we have a set on out bmw 540i 4.4 v8. they grip like mad!

My grammar nazi head has just exploded...too many....there/they're/their errors........heeeeellllpppp.
 
Caporegime
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well thats cheap chinese tyres for you! i work at a car garage and we have countless people comming in saying they got new tyres but there cars slide all over the place (someone in a new VW passat) its always chinese tyres! no matter hotmuch tread they have, there rubbish. get some good italian tyres or similar. dont buy chinese, indonesian or tiwaneese tyres xD we usually are always requested to replace there brand new tyres as sometimes there that bad they say there cars are undriveable! marangonnoi is a really good tyre to fit to ur bmw xD we have a set on out bmw 540i 4.4 v8. they grip like mad!

018_fry-argh.gif
 
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