bboy

I notice some people set a softer front tire than the rear (I thought you're suppose to have harder front than rear to avoid oversteer). Is this because the rear tire has a larger contact area so you can have the same /softer front?

lil-bump

iTrader: (89)

In some conditions you can run a softer front than the rear. It really helps with even tire wear during a long main

JetMD

iTrader: (1)

On our old track, everyone used to run softer on the rear mostly because we were always looking for rear grip and tire wear wasn't too bad. Now we are at a new location and wear is an issue. The rears wear very fast so most people run same front and rear or I have run softer in the front with pretty good success. At another track I go to, we always run softer in the front because it helps the cars turn alot better and there's tons of traction so the harder rear tires last a long time.

bboy

But won't you oversteer with a softer front?

Thanks for the clarification.

Sow&Steady

As you well know, tyres are not the only thing you use to set your car up. If you have to use softer fronts and harder rears to account for wear then set your car up accordingly so as not to oversteer.

JetMD

iTrader: (1)

lil-bump

iTrader: (89)

Ditto ( I'm just too lazy to type it) thanks for typing my words

bboy

So you mean you use a softer front to reduce tire wear? Interesting...

latemodel13

iTrader: (100)

No the rears wear more so if you run softer fronts you don't lose tire split. I ran 35 shore front and rear and in a 30 minute main would lose 3 mm of split.

Edgar Millenium

Hi!

Things are little more complicated. Today cars are design with tire split, more rear traction capable and a lot more stuff to set up. During mains rear tire tends to wear more, and cars are capable to have more rear traction than front, so you can use this advantage to have even tire wear or close to it, that way you car mantain more constant during the race. So basically you can run higher shore tires on the rear to also get more rotation on turns and keep even wear on the 4 tires.

bboy

Got it, let me try that next time.

Thank you everyone!

rx7ttlm

iTrader: (30)

In regard to nitro tires... Most people don't know that the actual construction and composition of the front and rear tires are diffrent.. The rear tires at least in the jaco lineup are much softer than the fronts.. notice you rarely chunk front tires on a nitro touring car? because they are harder than a similarly numbered rear.... so having a lower number front tire doesn't actually mean the tire is actually softer in the front..

Cheers,

Patrick

Edgar Millenium

Unless the tire is multi stage, the foam is the same, it only change the amount of foam rings it have, chunks on the rear is mostly caused to the traction and also can mean that the car needs more camber on that side. You can measure it with a shore reader and you will confirm it. I have one.

rx7ttlm

iTrader: (30)

First, foam front and rear isn't the same... , the construction front to rear is different foam.. call your tire supplier and ask if you don't believe me lol I can't speak for all the mfg's, but this does hold true for ellegi and Jaco.

Second, a durameter doesn't tell you what type of foam it is.. they may read similarly but the actual foam is different. and not just compound...Just like with your durameter you probably couldn't tell the difference between a green, a pink and a white foam tire.. why? they are all in the 30 range.. yet are different compounds right? the durometer just measures the deflection of the foam.. and assigns it a value.. degrees, thousandths of an inch, or what have you. in the end it can't tell you what the compound actually is or its adhesion properties.. different foam, yet reads the same..

Third, if you call the mfg and you don't believe them.. Call over to RC America, Ask for "Ralph", Aka Ralph Burch 2008 Winternats champ, and many time national champion and ask him...

Fourth, If you don't belive him and you think you know more than everyone else.. Try cutting any rear tire you have down to 26mm put it on the front of your car and tell me it doesn't rotate better and explain how the tire thats the same compound made the car free up so much...then tell me its the same compound...

Cheers...

Patrick B.
2008 Crewchief for Grand-Am #92 Mustang
2007 Team Leader Pro Formula Mazda
2006 Pro Formula Mazda National Champions

stefan

Here is a very good explanation of foam tires by Frank Calandra:

http://www.teamcrc.com/crc/modules.p...article&sid=27

Should answer a lot of questions.