[Rehaan]

Cambertires are tyres that are designed to be tapered towards the inner edge, making them mildly conical in shape. They were designed for track use where cars run a lot of negative camber - causing regular tyres to wear out unevenly.

What is camber?

Camber angle is the angle between the wheel and its vertical axis.

• If the top of the wheels are angled out further than the bottom \---/ it's called positive camber.
• If the top of the wheels are angled further in than the bottom /---\ it's called negative camber.

Note: Not all cars have adjustable camber.



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The advantage of camber?

(We're only going to talk about negative camber here)

In short, due to the way suspension and load-transfer works, a little negative camber greatly helps a car's cornering grip. This is the result of a larger contact patch of the tyre making contact with the road as the outer wheels are loaded up during a turn. More lateral grip = faster speeds around corners = faster lap times.

These guys are just doing it for style and beyond reasonable limits too:

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These guys are doing it purely for performance!

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The disadvantage of camber?

• Uneven / faster tyre wear.
• Reduced grip for straight-line braking and acceleration (since the tyre's contact patch isn't making max contact with the road whilst the car is going in a straight line).
• The car will become more likely to tram-line
• Heavier steering (?)

How does CamberTire solve this?

Available in 2, 3 & 4-degree options.

Not a very wide range of sizes available at the moment.

Because they're conical, they tend to roll inwards, which can be used to simulate toe-in, whilst the suspension can be set up for less toe-in -- giving the car a sharper turn-in characteristic.

Another advantage, from their website:

"Our innovation didn't stop with just adding camber, we looked deeper into cornering and
discovered that tire "roll" also caused a loss of handling ability. To compensate for this, we
added in what we call a "rocker" on both the inner and outer corners of the tire tread pattern.
As a tire "rolls" side to side from cornering g-forces, the shelf offers extra contact on the
rolling edge resulting in skid pad results exceeding 1G on a street legal tire!"

The tapered profile of a CamberTire:


There's also a cool spiral tread pattern, which provides a constant contact patch:

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But does it really work??

I'd like to believe it - at least in theory.

A few people have reviewed the tyres - but the problem is that no one has done any measured skidpad tests or timed laps!! Everything is on the bum-dyno.

Am still not 100% convinced, because, if you think about it:

• Stock tires w/ neutral camber : Contact patch lifts the inner edge on turns.
• Stock tires w/ negative camber : Contact patch becomes flat on turns.
• CamberTires w/ negative camber : Contact patch is flat at rest, and probably wants to lift the inner edge on turns once again?

However, if you run a -4-degree cambertire, you're supposed to run an even more negative camber (eg. -6-degrees), so maybe this makes a difference, along with the taller outside sidewall?

The company themselves had released these test results - but from what i can tell, the cambertires perform pretty much on par with the Advans, except the last row, where the cambertire is using a stickier "R" compound.



Video review from TheSmokingTire:

http://www.youtube.com/watch?v=Z5bT4hJ4B6M

Exiya's Build Journal (evoXforums.com)

Jeremy @ South Side Performance (evoXforums.com)

Jay Leno (video)

Something similar from another company : M&H Drag Radial

[kpzen]

R
Interesting read. Thanks for sharing.

Banking angle of the track is also a factor while deciding the camber angle of race cars.

While i was in Japan, i saw many crazy fellas running their toyotas with insane camber specs.
Wonder how they do high speeds on highway without any issue.

[sharc_biker]

Why do Piaggio Apes have positive camber?

I know it makes the steering light in tractors and offroaders.

But isn't that because it is a 4 wheeler and positive camber is on the front axle?
If yes, why does a Piaggio Ape has it on the rear axle? Better load bearing?


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[anachronix]

Interesting! Running a low PSI on the front tires running positive/negative camber usually helps, right!

Nice read, thanks for sharing!

[Rehaan]

Originally Posted by sharc_biker

But isn't that because it is a 4 wheeler and positive camber is on the front axle?
If yes, why does a Piaggio Ape has it on the rear axle? Better load bearing?

The Ape is designed to carry loads - so the suspension has probably been set up to be in an ideal position when under load. This is due to the type of independent rear suspension it is running.

It looks like it has positive camber when unloaded, but once its loaded up it probably comes in to a closer to neutral position. This ensures that the handling of the vehicle is not compromised and neither is the tyre-wear uneven when the vehicle is fully loaded.

cya
R

[dhanushs]

Originally Posted by Rehaan

Am still not 100% convinced, because, if you think about it:

Stock tires w/ neutral camber : Contact patch lifts the inner edge on turns.
Stock tires w/ negative camber : Contact patch becomes flat on turns.
CamberTires w/ negative camber : Contact patch is flat at rest, and probably wants to lift the inner edge on turns once again?

There are various forces acting while taking a turn, like: Force due to slip angle, camber thrust etc.. A negative camber is best preferred for these forces to be "in-favor" to the vehicle taking the turn.

Also, there is body roll when a vehicle takes a turn. The effect of this body roll is to induce a positive camber, which is not favorable whist cornering. The best solution for this is to have a negative camber to start with.

So, Rehaan, IMO, by having Camber tyres, the benefit is not only the contact patch, but entire dynamics involved in cornering is benefited.

Originally Posted by sharc_biker

Why do Piaggio Apes have positive camber?

IMO, a positive camber loads the inner bearing more.. Or, the center of the tyre will be in line with the inner wheel bearing, which I think will help the vehicle track true, better load carrying, tyre wear etc..

[W.A.G.7]

Good technical insight about these tyres. I always had questions in my mind after seeing the Ape's running around with +ve camber tyres. But I have seen a lot of Ape's with outer rim tyre wear, maybe because most of the times, the vehicle is not that loaded enough to cause the setup to settle like this --> |--| Hence many times, I see they are running like this --> \--/ causing uneven wear on the outer part of the tyre.

I also never knew that conical shaped tyres existed. Thanks for sharing the knowledge. The first Toyota pic is insane, how does he manage to drive that car around?

[Sivasankar]

@Rehaan - Thanks for such an informative article.

I think the Fiat Linea T-Jet runs on a few degrees of negative camber on the front wheels. Am I right?

And BMWs also run on positive camber in their rear wheels, right?

[akshay4587]

Originally Posted by Sivasankar

@Rehaan - Thanks for such an informative article.

I think the Fiat Linea T-Jet runs on a few degrees of negative camber on the front wheels. Am I right?

And BMWs also run on positive camber in their rear wheels, right?

I think yes,at least my Linea MJD has a certain degree of negative camber.
When i first got it,i thought it was a fault,but then i realized its common across all Linea's,may be it is one of the contributing factors for the excellent handling.

[PapaBravo]

@Rehaan. Wonderful write up. Two question though :

1.How much does the camber of a car change from unladed to fully loaded state ?

2. Will the cars with default Negative Camber not tramline in fully loaded conditions? This would defeat the purpose of having a camber in the first place.

Regards

[karan561]

Firstly Thank you Rehaan for this informative thread

Adjusting the camber can not even make the car perform fastest through the corners but also slowest through them for this;



From this page:

Drift camber tire setting;

Where the Front-wheel is 3 to 4 degrees of negative camber, which helps put the tread flat on the ground when under side load.

How it works:

The tire’s carcass wants to flex and lift the inside of the tread off the ground; as the car rolls, it also wants to tip the tire to where the inside of the tread is being lifted off the ground. The car’s suspension geometry tries to make up for some of this, but it can’t totally compensate — running negative camber compensates for this.

Where as Rear-wheel camber is close to zero as possible. This will usually give the car the best tire wear and best forward bite.

If one wants a little more side grip, you can also run some negative camber, but usually no more than 1 degree negative.

Originally Posted by Sivasankar

And BMWs also run on positive camber in their rear wheels, right?

BMWs rear wheels normally run on a negative 2 degrees camber

[EagleEye]

Originally Posted by sharc_biker

Why do Piaggio Apes have positive camber?

I know it makes the steering light in tractors and offroaders.

But isn't that because it is a 4 wheeler and positive camber is on the front axle?
If yes, why does a Piaggio Ape has it on the rear axle? Better load bearing?

Attachment 1071548
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It's interesting, because Piaggio use the same positive camber on their aircraft as well.

Here's a picture of a Piaggio Avanti:

[swarnava.m]

A little OT here. Couple of posts where people have spoken about Linea and Beemers having negative camber to start with.. What happens when regular tyre shop guys do wheel alignment for these cars? Are they aware of this? Will they not set the camber to zero?
Sorry if this is a stupid question.

[ImprezaFan]

Thanks for the knowledge, Rehaan.

Originally Posted by Sivasankar

@Rehaan - Thanks for such an informative article.

I think the Fiat Linea T-Jet runs on a few degrees of negative camber on the front wheels. Am I right?

And BMWs also run on positive camber in their rear wheels, right?

My ritz runs on 195mm tyres and I've always (visually) felt that the rear tyres have a slight negative camber. Have seen this in swifts with >185mm width. Don't know if there is a default negative camber in all stock cars (which becomes prominent with wider tyres). Could somebody please confirm?

Is there a relationship such that (all) FWD cars have rear tyres negatively cambered (or vice versa)? If yes, why?

[Arch-Angel]

Nice article about Camber setups Rehaan. So Negative camber is for handling and positive camber is for load bearing. But doesn't a neutral setup provide the best of both worlds? Because in case of either greater loads or lesser loads either of them are bound to fail in its required purpose.