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Discussion Starter #1
I have a set of Kuhmos and ordered two more for my first rally.

I know it is a no-no in road racing using different tires front/rear so, I was wondering if it is the same on gravel.

Tirerack changed the stock date once since I ordered, and I have to consider other options if they can't deliver. The first option will be probably Silverstones.

TIA,

Carlos.

ps. John V where are these cheap Finn tires? prices? delivery?
 

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No problemo using different tires F/R if the car and situation calls for it. We sometimes use narrower tires on the front of our Starion RWD to get more bite for steering, and wider in the rear for straight-ahead traction and to make the rears float easier in turns (intentional oversteer). All this depends on your car and the traction situation; in mucky mud or snow, I would go as narrow as possible F and R as the game is to fight for traction, ANYWHERE. And, you will have one set of tires that the spare won't fit exactly, unless you carry 2 spares.

Mark B.

PS, IF AWD I would think this is a bad idea, unless the tires were exact same outer diameter; otherwise the center diff is working all the time.
 

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Discussion Starter #3
Mark,

I was thinking more on the thread pattern, but I guess you answered my question anyway.

Thanks,

Carlos.
 

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Carlos,

Uniform tire sidewall behavior (stiffness, flex and lateral deformation) all around is very important to uniform and predicatable handling. Gravel is no exception. Tire sizes and tread patterns could be varied, but F/R sidewall behavior should be kept uniform. This is a funtion of the Manufacturer's casing design and construction, so the best way to keep things uniform and predictable is to use the same tires F and R.

That's why I'm looking forward to John V's Import Retreads on Michelin casings. I know they will match the lateral behavior of the Michelin's I already have even though the tread pattern will be somewhat different.

Getting a good Casing/Sidewall match from different Manufactuers would be very difficult, and perhaps even risky. I'd keep them the same.

Rich Smith
 

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Check the rule book. I don't have time at the moment, but I think retreads are specifically prohibited. I remember this because I wanted to use Bandag off road tires and they are a retread.
Richard
 

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Retreads Not Prohibited

>Check the rule book. I don't have time at the moment, but I
>think retreads are specifically prohibited. I remember this
>because I wanted to use Bandag off road tires and they are a
>retread.

Richard,

I find No Prohibition against retreads in the current SCCA on-line rule book, and I've seen Colway's from England rallied in past years. (They just kinda got priced out by Silverstone and Kumho).

I'm looking forward to John V's lower cost retreads on Michelin casings from Finland.

Rich Smith

Vive "Pro-le-Ralliat"
 

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Discussion Starter #7
RE: Retreads Not Prohibited

Rich,

It makes sense what you said about the side wall and construction.

The problem is that my dead line is coming really fast. I can't go to a rally without a spare!!!

I just want to get a feeling on what to expect by using different tires.

Honestly, I hope that I don't have to do this.

Thanks again,

Carlos.
 

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I'd give you the same answer with different treads or even different casings/brands F to R. At 100AW we ended up with Kuhmo's up front and Michelin assymetrics in the rear. It was a good combo. The handling did not suffer one bit; the Kuhmo's up front helped the turn-in bite and the Michelins worked well in the back for traction in the very hard packed dirt (which overheated the Kuhmo's badly). It was a better combo than Kuhmo's all around or Michelins all around. It all depends on the car and the conditions.

Mark
 
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