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View Full Version : Wheel Alignment - Odd Tyre Wear



Zilli
16-06-2008, 09:26 PM
Hey all, im getting so feathering of the outside edge of the front left tyre, is this a toe adjustment issue you reckon? it seems to be the outside of the left and slightly the inside of the right....

aaronng
16-06-2008, 09:33 PM
what are your alignmetn settings?
usually not toe because toe will self centre

T-onedc2
16-06-2008, 09:37 PM
do you perform a lot of tight right hand turns? eg. u-turns or tight roundabouts

Zilli
16-06-2008, 09:39 PM
lost the paperwork Aaronng.... its stock settings, but bout 2.x - camber...

T-onedc2 i noticed this after hitting wakefield a month or so ago... ive put 200kms on it since...

what else would cause this sort of wear if its not toe?

bennjamin
16-06-2008, 09:41 PM
since "Hitting" wakie ?
that means you still have the semis on ? If thats right , wakie is mostly right hand turns , inner left hand edge of the tyres is the contact patch and wear.

otherwise ?

T-onedc2
16-06-2008, 09:41 PM
lost the paperwork Aaronng.... its stock settings, but bout 2.x - camber...

T-onedc2 i noticed this after hitting wakefield a month or so ago... ive put 200kms on it since...

what else would cause this sort of wear if its not toe?
if Wakefield is travelled in a clockwise direction then most corners are right turns giving same result, don't know the track myself

aaronng
16-06-2008, 09:43 PM
camber, castor?

Zilli
16-06-2008, 09:54 PM
You know what i mean Ben.... yeh still on Semi's... i dont have street tyres

So what you're sayig is the wear is probably as a result of the heavy right hand turn bias of the track?

Dont know what the castor setting is to be honest aaron

bennjamin
16-06-2008, 09:55 PM
i think so. You did have that wear on the day ~

IMO take the tyres off before you ruin them. Then rotate them L/R and then F/R for the next track day

Zilli
17-06-2008, 07:50 AM
anyone else have any opinions?

DLO01
17-06-2008, 12:07 PM
Too much Toe in. :thumbsup:

DLO01
17-06-2008, 12:10 PM
Wear Pattern Name: One-Sided Shoulder Wear 2 - Feathering.
Characteristics: Rapid wear on one tread shoulder. Tread shoulder area has a "scrubbed" or "feathered" appearance. Excessive toe-in will feather the outside shoulder, excessive toe-out will feather the inside shoulder.
Possible Causes: 1. Excessive toe-in or toe-out setting. 2. Consistent, severe cornering. This is a common wear pattern on the near side front tyre on many four-wheel-drive wagons with live front axles.

aaronng
17-06-2008, 12:11 PM
lost the paperwork Aaronng.... its stock settings, but bout 2.x - camber...

T-onedc2 i noticed this after hitting wakefield a month or so ago... ive put 200kms on it since...

what else would cause this sort of wear if its not toe?

Depends on the tyre shop too. Some like to put 2.0mm toe in eventhough stock specs on the Euro is 0mm toe in. I've seen another put 4.0mm toe in on a Mazda which is nowhere near stock! So unless you have the printout, then it is not easy to diagnose.

If you have uneven tyre wear after Wakie, make sure you rotate your tyres. If yours are directional, then swap them front to back.

Zilli
17-06-2008, 12:34 PM
thanks boyts, i thought it had something to do with toe... buta printout would be ideal i suppose...

cheers

TBS33N
17-06-2008, 02:53 PM
make sure all your bushes are intact and not cracked or worn. This can cause uneven tyre wear.

eg5civic
17-06-2008, 03:23 PM
eeek after reading this thread i decided to check my tires and to my surprise found my left front to be nearly bald.... all other tyres are around 40% at least...

Looks like new tyres are in order already :(

DLO01
17-06-2008, 03:35 PM
Make it a habit to always check your tyre wear regulary. :thumbsup:

Its only a quick visual inspection, but can save you a lot of money.

Zilli
17-06-2008, 03:45 PM
anyone know if a good place on the north side of Sydney for a wheel alignment?

ive had bad experiences with the Bob janes etc around here...

aaronng
17-06-2008, 04:29 PM
Tyre power? Call up and ask if they do laser alignment. And that you want your own settings to be put in. Mark and Wallings at Ryde is good.

Zilli
17-06-2008, 04:34 PM
where is tyre power?

Mark and Wallings is heaps close, just weary of it sitting so damned low... was hoping for somewhere that can cater

traumatized
17-06-2008, 08:57 PM
how do you know what settings it should be at?

aaronng
17-06-2008, 10:30 PM
how do you know what settings it should be at?

Stock euro
Front
Toe: 0mm total (tyre shops tend to put 2mm total toe in)
Camber: 0 degrees

Rear
Toe: 2mm total toe in
Camber: -1 degree


If it was me,
Front
Toe: -1mm total toe out
Camber: -1 degree

Rear
Toe: 1mm total toe in
Camber: -1 degree

Of course, you can't adjust front and rear camber without camber kits.

traumatized
17-06-2008, 10:36 PM
^thanks aaron

loki78
19-06-2008, 12:12 AM
I recently had to change my tyres because the shoulder of my front left tyre was bald which sounds pretty similar to what Zilli is noticing on his tyres. Got a wheel alignment done and was told that my front camber and caster is crooked causing the uneven tyre wear.

My current figures are:
Front Caster
LHS +1 degrees 44 minutes
RHS +0 degrees 59 minutes

Front Camber
LHS -0 degrees 33 minutes
RHS -1 degrees 10 minutes

Ther person who did my alignment told me that I'll need to spend around high $1k to get it fixed and told me to leave it as is and just keep an eye on the tyres.

What do you guys think I should do? Just keep rotating my tyres? Does it really cost that much to get a camber kit setup properly?

Forgot to mention my car is an EK hatch back.

JohnL
19-06-2008, 10:49 AM
Camber (within reason) on it's own isn't a huge generator of tyre wear, but add significant toe to significant camber and the wear multiplies (i.e. camber X toe creates a lot more wear than toe or camber on their own).

You may get reasonable wear on both tyres even if you have unequal camber but with zero toe. However, if you have uneven camber as well as significant toe then the tyre with more camber will most probably wear a lot faster than the other tyre.

gbang007
19-06-2008, 05:22 PM
yeh i checked mine and i have real bad uneven wear. done about 15,000-20,000km on proxes 4 and the front inner shoulder is pretty much bald. all the rest looks perfectly fine, like new but the two front inner shoulders are bad. time for new tires. im on 17's for an ek. had a wheel alignment when i got the wheels put on but nothing since. would they be able to tell me if it was out? i haven't been thrashing it or anything. its lowered too. by about 1.5".

chargeR
19-06-2008, 05:29 PM
What do you guys think I should do? Just keep rotating my tyres? Does it really cost that much to get a camber kit setup properly?

I agree with JohnL, if you make sure you toe is set correctly (zero at the front) then the small amount of camber you have should not cause any tyre wear problems especially if you are religious with your tyre rotation. Camber on its own causing significant tyre wear is a myth, as JohnL mentions.

bennjamin
19-06-2008, 05:32 PM
yup TOE is the main culprit for tyre wear.

Keep rotating tyres , keep your tyre pressure checked and up and get an alignment once in awhile :) Tyres should last a long time

tknova
19-06-2008, 06:53 PM
I've got a quick question re honda accord euro wheel algnment

I'm running -1 camber & 0.00m toe on the front wheels and getting great tyre wear

The rear tyres are running -3 camber & 0.00 toe and getting a very bad feathering effect on the inside of the rear tyres.

I have an ingall rear camber kit but cannot make the camber any more positive or i'll hit the rear 1/4 panels,

I'm happy to live with the accelrated camber wear but the feathering makes the tyres extremely loud.

What's the best toe setting i should run with -3 camber to stop the feathering effect?


CHeers ! :)

aaronng
19-06-2008, 07:14 PM
I've got a quick question re honda accord euro wheel algnment

I'm running -1 camber & 0.00m toe on the front wheels and getting great tyre wear

The rear tyres are running -3 camber & 0.00 toe and getting a very bad feathering effect on the inside of the rear tyres.

I have an ingall rear camber kit but cannot make the camber any more positive or i'll hit the rear 1/4 panels,

I'm happy to live with the accelrated camber wear but the feathering makes the tyres extremely loud.

What's the best toe setting i should run with -3 camber to stop the feathering effect?

CHeers ! :)
For the rear, I've had good toe but camber was -3 and it still wore the inside. What are the offset of your rims? You should roll your guards or raise your car up or get rims with a higher offset if you want to get the camber back to spec.

tknova
21-06-2008, 06:05 PM
For the rear, I've had good toe but camber was -3 and it still wore the inside. What are the offset of your rims? You should roll your guards or raise your car up or get rims with a higher offset if you want to get the camber back to spec.


I'm got a 19 inch wheel with a +45 offset

I'm going to lip the rear guard to try and suqqze a little bit more positive camber out.

The accelrated inside tyre wear (camber) i'm happy to deal with, it's just the feathering (been told is due to toe setting) which makes the rear tyres sound like 4x4 tires (feathering effect)

I've read that toe is the main culprit for feathering,

As stated i', running 0.00m toe on the rear, i now understand i should be running atleast -1or -2 toe,

But, running with -3 camber, should i run a different toe setting to stop the feathering? or run at -1m -2m toe as recommended.

The only problem i see, is that i'm running 0 toe on the rear at the moment. Abd the feathering is very bad, the rear tyre on the inside has now got a 'wave' effect.

I have a feeling that -1 or -2 worth of toe will not fix this? or will it fix the problem?

Ohh yeh, for best tire wear should you run -1 or -2 toe? or is 0 toe on the rear going to get back tire wear?

Help is appricated!

Cheers :)

aaronng
21-06-2008, 06:22 PM
Your rear is meant to be +1mm toe in on each side! Not toe out by -1mm.

What is the width of the rims and the tyre size?

eg5civic
21-06-2008, 06:48 PM
Does the +1mm of toe on the rear effect how much they wear the tyres would get.. as in increase the rate of wear or is it more drastic like +2 or +3mm that cause excessive wear

aaronng
21-06-2008, 10:28 PM
Does the +1mm of toe on the rear effect how much they wear the tyres would get.. as in increase the rate of wear or is it more drastic like +2 or +3mm that cause excessive wear

Not sure about other cars, with the Euro, it comes with +1mm toe in (total toe in +2mm) and -1 degree camber on the rear as stock. With this setup, the rear wears evenly and slower than the front tyres, which have 0mm toe in (or up to +2mm toe in depending on where you do your alignment) and 0 degrees camber.

tknova
22-06-2008, 01:19 PM
Your rear is meant to be +1mm toe in on each side! Not toe out by -1mm.

What is the width of the rims and the tyre size?

19x8, 45+ offset, running on 235/35/19'.

Would be awesome if you could post up the recommended specs for me aaronng. I'll print it out and give to the wheel alignment guys to check out.

JohnL
22-06-2008, 02:44 PM
Camber on its own causing significant tyre wear is a myth, as JohnL mentions.
Well, IMO, yes and no. If you run a lot of neg camber then inner edge wear is bound to be greater (I'd suggest 3° is a lot of camber for a road car, and especaially for a Honda fitted with double wishbone suspension).

It's not only toe that can multiply camber related wear, if you habitually accelerate hard and brake hard then the inner edges of the front tyres will wear more quickly, especially with wider tread and/or lower profile and/or higher inflation pressure (and/or more camber, of course). This may especially be so with a lot of hard braking with associated forward weight transfer to the (already heavily loaded with FWD) front wheels and associated nose dive.

Hard braking generates the highest forces and wear per second that the tyres will typically ever see (with the exception of gratuitous wheelspin). Due to neg camber gain with suspension bump motion, nose dive under hard braking further increases dynamic neg camber (just when the treads are seeing their highest loadings) and thus camber wear. This problem increases inner edge wear, but also decreases front wheel grip under brakes (not good), and is greater with double wishbone suspensions than with Mac struts because with double wishbone the front wheels will gain a lot more neg camber with nose dive than will Mac struts (i.e. double wishbone suspensions typically gain a lot more neg camber in bump than do Mac struts). So, with double wishbone suspensions it's a good idea to avoid excessive static camber (there are other reasons too why a lot of static neg camber isn't a good idea, to do with cornering and tractive grip generated - or not- at the inside front contact patch).

Typically, cars (including many Hondas) with double wishbone suspensions ('short / long arm', or SLA suspension) don't need nearly as much static neg camber as cars fitted with Mac struts. Mac struts tend to suffer from a very poor camber curve, i.e. they don't gain nearly enough neg camber with bump motion, and this equates to too little camber gain in roll so the outside front wheel tends to run at excessive pos camber in roll, unless a lot of static neg camber is used (which adversely affects front wheel grip in acceleration and braking, i.e. large neg camber settings aren't a 'good thing' in all areas of chassis dynamics, instead being a compromise for a compromised design).

Also, due to design constaints Mac struts tend to have way too much KPI (i.e. inward lean of the steering axis), which creates a steered pos camber gain at the outside front wheel (i.e as the outside front wheel is turned into the corner it gains pos camber, more so with greater KPI), so more static neg camber is required to counteract this.

SLA suspensions tend to have less KPI and generally require less static neg camber to compensate for both KPI and camber curve because both camber curve and KPI are typically much better than with Mac struts.

These problems can be so bad with Mac struts that in some racing applications Mac struts can have not only quite severe static camber angle but also absolutely huge amounts of caster angle (I've heard of up to 20° of caster in some touring car categories!!!) designed in to counteract the Mac strut problems of poor camber curve and excessive KPI.

The moral of the story is that you shouldn't run large camber angles on an SLA suspended car just because you see a lot of racing sedans run large camber angles. Nearly all of those cars will have Mac stut front suspensions and thus will require substantial static camber angles (to compensate for the shortcomings of the Mac strut design) that would most probably be counter-productive for cars with a good SLA design (read many Hondas).

aaronng
22-06-2008, 03:13 PM
19x8, 45+ offset, running on 235/35/19'.

Would be awesome if you could post up the recommended specs for me aaronng. I'll print it out and give to the wheel alignment guys to check out.

235 and +45 is a little too far out. +50 or +55 would have been better, but i am not sure if it would rub against the strut. I'd recommend going for 225 width if you can get that in 19". After all, the Euro is not a car that needs that much tyre width.

Front:
Toe: 0mm (some tyre shops list +1mm toe in)
Camber: 0 degrees
Can't remember front castor, but you can't adjust it anyway with stock suspension.

Rear:
Toe: +2mm total toe in (+1mm on each side)
Camber: -1 degrees each side.

Be aware that going to -1 from -3 degrees rear camber would probably cause rubbing.

chargeR
22-06-2008, 07:31 PM
Well, IMO, yes and no. If you run a lot of neg camber then inner edge wear is bound to be greater (I'd suggest 3° is a lot of camber for a road car, and especaially for a Honda fitted with double wishbone suspension).



True story, I have nearly 5 degrees of negative camber at the front of my car and whilst my street tyres are wearing well they are definitely wearing slightly faster on the inside edge. To put it in perspective I have had the tyres (Bridgestone RE001) on for around 25,000kms with 11,000kms with -5 camber and I expect them to last around 10,000kms more.

gbang007
23-06-2008, 04:16 PM
gonna get new tyres in the next month or so coz of bad wear at the front. tyre pressure is fine. my car is lowered about 1.5". They were balanced when i got my tyres on about 2 years ago. Haven't really paid attention till a couple of months ago when it was too late. Anyway, should i just get the new ones on and get them to balance and then just keep my eye on them for uneven wear? or what can i do to prevent it getting to that stage again?

aaronng
23-06-2008, 04:19 PM
gonna get new tyres in the next month or so coz of bad wear at the front. tyre pressure is fine. my car is lowered about 1.5". They were balanced when i got my tyres on about 2 years ago. Haven't really paid attention till a couple of months ago when it was too late. Anyway, should i just get the new ones on and get them to balance and then just keep my eye on them for uneven wear? or what can i do to prevent it getting to that stage again?
What are the current alignment settings on your car?

gbang007
23-06-2008, 04:28 PM
NFI! lol. i just got new wheels put on like 2 years ago back in the noob days.


What are the current alignment settings on your car?

JohnL
24-06-2008, 09:31 AM
True story, I have nearly 5 degrees of negative camber at the front of my car and

That's an awful lot of camber. IMO the only time it's going to be productive is when cornering very hard with a lot of weight transfer to the outside front tyre, but only if you have enough body roll to cause that 5° of camber to be negated and for the contact patch to be presented to the road 'squarely' under full roll (and of course the inside front camber will be utterly terrible rendering the inside front tyre almost useless for much of the corner, nearly all front grip will have to be generated by the outside front only).

If you have a fair degree of roll stiffness you might never even get that outside front contact patch presented squarely to the road, meaning the full potential grip from either of the front tyres may never be realised, even at mid corner with max body roll (?).

Keep in mind too that with body roll the camber of the inside front tyre becomes even more disadvantageous, and the more so the more the static neg camber is. With FWD we rely more upon inside front grip then RWD cars do, so we should be careful not to compromise inside front grip too much with excessive neg camber angles.

Having the inside front runing on it's inner edge of tread won't be very good for either lateral front grip (read understeer), nor for longitudinal traction exiting corners (read inside front wheelspin). High levels of neg camber will compromise front tyre braking performance, and this becomes even worse with nose dive under hard braking. This is more problematic for double wishbone designs than for Mac struts because double wishbone suspensions gain more neg camber with bump motion (as you get with nose dive). Under brakes, you have the static neg camber + any neg camber gain from the bump motion, which isn't all that much with Mac struts but substantially more with double wishbone (typically), so with substantial static neg camber to start with you may end up braking on effectively quite small front contact patches...

One of the main benefits of a well designed double wishbone suspension is that less static neg camber is required to maximise dynamic performance than with Mac struts (and performance will be greater than Mac strut, all else being equal), but with so much camber I suspect you're suspension might be being held back nearer Mac strut type performance...

aaronng
24-06-2008, 11:03 AM
NFI! lol. i just got new wheels put on like 2 years ago back in the noob days.

Get an alignment done and ask for a printout. Putting on new tyres with NFI alignment is just asking for wear if the previous set of tyres were chewed through because of alignment.

chargeR
24-06-2008, 04:41 PM
That's an awful lot of camber. IMO the only time it's going to be productive is when cornering very hard with a lot of weight transfer to the outside front tyre, but only if you have enough body roll to cause that 5° of camber to be negated and for the contact patch to be presented to the road 'squarely' under full roll (and of course the inside front camber will be utterly terrible rendering the inside front tyre almost useless for much of the corner, nearly all front grip will have to be generated by the outside front only).

If you have a fair degree of roll stiffness you might never even get that outside front contact patch presented squarely to the road, meaning the full potential grip from either of the front tyres may never be realised, even at mid corner with max body roll (?).

Keep in mind too that with body roll the camber of the inside front tyre becomes even more disadvantageous, and the more so the more the static neg camber is. With FWD we rely more upon inside front grip then RWD cars do, so we should be careful not to compromise inside front grip too much with excessive neg camber angles.

Having the inside front runing on it's inner edge of tread won't be very good for either lateral front grip (read understeer), nor for longitudinal traction exiting corners (read inside front wheelspin). High levels of neg camber will compromise front tyre braking performance, and this becomes even worse with nose dive under hard braking. This is more problematic for double wishbone designs than for Mac struts because double wishbone suspensions gain more neg camber with bump motion (as you get with nose dive). Under brakes, you have the static neg camber + any neg camber gain from the bump motion, which isn't all that much with Mac struts but substantially more with double wishbone (typically), so with substantial static neg camber to start with you may end up braking on effectively quite small front contact patches...

One of the main benefits of a well designed double wishbone suspension is that less static neg camber is required to maximise dynamic performance than with Mac struts (and performance will be greater than Mac strut, all else being equal), but with so much camber I suspect you're suspension might be being held back nearer Mac strut type performance...

Good observations JohnL :thumbsup:, however I simply posted up my experience with tyre wear to demonstrate that camber is not the evil that many presume it to be :), which pertains to the thread topic, not to get a lecture on how terrible my suspension setup is :p.

My suspension is being held back to Macpherson strut performance because my front suspension is Macpherson strut :p. I can nearly lift my inside front wheel on track so I am not super worried about the very poor camber that the inside wheel has. You are correct though, tyre temps suggest that my camber is a little excessive with higher inner temps and a differential of a few degrees across the tread. Nothing extreme though and the setup works.

eg5civic
24-06-2008, 07:42 PM
Get an alignment done and ask for a printout. Putting on new tyres with NFI alignment is just asking for wear if the previous set of tyres were chewed through because of alignment.

Hey i got my alignment done today and new re001's all round

What confused me was they llft the camber and toe as they were on the rear when i got a 4 wheel alignment... all they changed was .1mm of cross toe

Sheets attached at the bottom

Also found why my front left tyre wore quickly...... +9mm of toe :P

Oh and to hurt me even further they ut my car as a 1.5L SOHV

WTF is SOHV... its clearly DOHC :p

aaronng
24-06-2008, 08:09 PM
Hey i got my alignment done today and new re001's all round

What confused me was they llft the camber and toe as they were on the rear when i got a 4 wheel alignment... all they changed was .1mm of cross toe

Sheets attached at the bottom

Also found why my front left tyre wore quickly...... +9mm of toe :P

Oh and to hurt me even further they ut my car as a 1.5L SOHV

WTF is SOHV... its clearly DOHC :p
Looks good. I wonder why they didn't adjust your rear toe. The stock suspension should have some limited adjustment of rear toe....

eg5civic
24-06-2008, 08:11 PM
yeah thats what i thought.... do you think i should ring and question them on it or just wait the month or so till i get my coilovers

aaronng
24-06-2008, 08:21 PM
yeah thats what i thought.... do you think i should ring and question them on it or just wait the month or so till i get my coilovers

I might be wrong though, I'm not 100% sure of your Civic. If you do have the facility, get them to readjust it under "warranty". Many tyre places let you do a free realignment if there are problems if you don't like what they did. When you get your coilovers, you will have to redo your alignment because you are changing your car's height.

eg5civic
24-06-2008, 08:25 PM
Yeah they shouldn't wear that much over the period of the month right.....

Cheers for that

aaronng
24-06-2008, 08:58 PM
Your left rear toe is worrying...

eg5civic
25-06-2008, 04:18 PM
Hmm tis my thinking exactly... i'll give them a call now

Edit- and he says to bring it in tomorrow arvo, after i explained twice it was the rear tow not the camber that needed adjusting:rolleyes:

aaronng
25-06-2008, 05:25 PM
The rear toe has to be equal on both sides, because it doesn't have steering like the front, which helps it self-centre. For the front, it doesn't matter if both sides have unequal toe, as long as the camber and castor are correct, because the steering self-centers. You just worry about total toe for the front.

JohnL
25-06-2008, 06:07 PM
, not to get a lecture on how terrible my suspension setup is :p.

Aplologies, not meant as a lecture, just observations on camber. So many people use so much, seemingly for no better reason than that they see a lot of racing sedans using a great deal, without really understanding why nor what the compromises might be.

I do stand by my asssertion that cars with double wishbone suspension require and benefit from less static camber than cars with Mac struts.


My suspension is being held back to Macpherson strut performance because my front suspension is Macpherson strut :p.

I feel for you, really I do! Having bagged them so hard, Mac struts can be set up to work OK, amd a well set up Mac strut will outperform a poorly set up anything else...


I can nearly lift my inside front wheel on track so I am not super worried about the very poor camber that the inside wheel has.

IMO it's not such an issue at mid corner at high levels of weight transfer with the IF largely unloaded, but leading up to mid corner when lateral acceleration and weight transfer are less and we are depending to some degree on IF grip then poor IF camber can contribute to understeer.


You are correct though, tyre temps suggest that my camber is a little excessive with higher inner temps and a differential of a few degrees across the tread. Nothing extreme though and the setup works.

Good! Mac struts can work better than they have any theoretical right to, though I still contend, all else being equal, a good double wishbone will always beat a good Mac strut...

chargeR
25-06-2008, 06:37 PM
@ eg5civic: you should definitely get that toe sorted. 3mm of total toe in at the rear of my car was enough to cause inner shoulder wear with moderate camber after not a lot of k's.


Apologies, not meant as a lecture, just observations on camber. So many people use so much, seemingly for no better reason than that they see a lot of racing sedans using a great deal, without really understanding why nor what the compromises might be.


No need for apologies I found your post and interesting read :thumbsup:. I was forced into running the amount of camber I have due to using suspension designed for N1 racing in Japan, and I try not to kid myself that it is the perfect setup :p. And your observations about grip in the lead up to mid corner when the outside front is not fully loaded are quite astute as this phase of the corner can be a slight problem in my car, I am thinking about trialling my car with no front sway bar to see what happens :).

Zilli
25-06-2008, 10:20 PM
guys, back to my original issue... although some great reading by some obviously very knowledgable people...

Ive been noticing a large amount of roar when the car is riding, and im thinking my wheel bearings are shot... could this be contributing to my issue? just a thought that popped into my head, im yet to get the time to go and get the wheels aligned.

aaronng
25-06-2008, 11:18 PM
guys, back to my original issue... although some great reading by some obviously very knowledgable people...

Ive been noticing a large amount of roar when the car is riding, and im thinking my wheel bearings are shot... could this be contributing to my issue? just a thought that popped into my head, im yet to get the time to go and get the wheels aligned.

I would blame the roar on your tyres first, if you are still running the semis.

tknova
26-06-2008, 07:04 AM
guys, back to my original issue... although some great reading by some obviously very knowledgable people...

Ive been noticing a large amount of roar when the car is riding, and im thinking my wheel bearings are shot... could this be contributing to my issue? just a thought that popped into my head, im yet to get the time to go and get the wheels aligned.

Also possible that your tyres are shot due to toe settings, I have the same problem, rear tyres are loud as due to incorrect toe and are now featherd.

JohnL
26-06-2008, 09:39 AM
And your observations about grip in the lead up to mid corner when the outside front is not fully loaded are quite astute as this phase of the corner can be a slight problem in my car,

This is one reason why front drive cars have the 'roll couple' (i.e. front / rear relative roll stiffness bias) biassed toward the rear (i.e. stiffer in roll at the rear). Less front roll stiffness results in less lateral weight transfer at the front and more at the rear (i.e. the IF remains more heavily loaded for longer in the corner).

This gives not only better traction to the driving wheels (the IF in particular) exiting corners, but more front grip in total for both trail braking and lateral grip going into the corner (needed with very front heavy FWD cars). This is because having the two front wheels more equally loaded is in effect the same as having more 'rubber on the road' at the front and relatively less at the rear. However, having one of those front wheels at a very poor camber is reducing 'rubber on the road', and reducing front grip.

This is why large caster angles are a 'good thing'. i.e. caster creates a steered gain in neg camber at the OF and a steered gain in pos camber at the IF. Both these steered camber gains are what we want to keep the treads more squarely presented to the road (i.e. maximise front contact patch size).

This means that with larger caster angle we can use less static neg camber, as much as we can engineer in without creating mechanical problems is usually the 'right' amount (there are limits on what is practically posssible). Some Mac strut suspended racing cars use as much as 20° of caster (yes really!), which is why if the power steering stops working the race is usually over...


I am thinking about trialling my car with no front sway bar to see what happens :).

My car (CB7 Accord) is only a road car, but I removed the front ARB and am very happy with what this has done. Body roll is increased noticably but not nearly as much as I was half expecting (Konis help to keep roll under control in 'shorter' corners, though not in 'longer' corners such as roundabouts etc). Understeer is definitely reduced and general handling balance improved. The car needs a stiffer rear ARB, when funds allow...

eg5civic
26-06-2008, 04:27 PM
Well i went back and asked them and the guy reckons he can't fix it as there is no toe or camber adjustment in the rear... i can understand camber but the toe??

Does anyone know if an EG Si Hatch has rear toe adjustment.... if so pic with the adjuster circled so i can point it out to the guy :)

chargeR
27-06-2008, 11:17 AM
Well i went back and asked them and the guy reckons he can't fix it as there is no toe or camber adjustment in the rear... i can understand camber but the toe??

Does anyone know if an EG Si Hatch has rear toe adjustment.... if so pic with the adjuster circled so i can point it out to the guy :)

Not sure if this will help but here is the section regarding toe adjustment from the Helms manual:

http://img204.imageshack.us/img204/9003/egtoeadjustmenten8.jpg

gbang007
11-07-2008, 12:51 AM
ok guys,

got my new tyres and printout of the alignment. my previous tyres wore on the inner shoulders of the front. im gonna get a different place to align as the place which i got my tyres from wanted to rip me off. my toe is extremely owrrying, even the rears so should i ask them to adjust that aswell? coz the previous tyres wore evenly on the rears.

http://s218.photobucket.com/albums/cc104/gbang007/?action=view&current=al.gif

aaronng
11-07-2008, 08:35 AM
ok guys,

got my new tyres and printout of the alignment. my previous tyres wore on the inner shoulders of the front. im gonna get a different place to align as the place which i got my tyres from wanted to rip me off. my toe is extremely owrrying, even the rears so should i ask them to adjust that aswell? coz the previous tyres wore evenly on the rears.

http://s218.photobucket.com/albums/cc104/gbang007/?action=view&current=al.gif

Wow, yes, adjust front and rear. Go to a Bridgestone Tyre Centre. They charged me $65 for front and rear. Front alone is $55 I think.

Go for 0mm front total toe, and +1mm rear total toe in, and you'll be surprised compared to how your car handles now. Do you have a camber kit to adjust camber?