Replacing 2 tyres only? - FYI

[rahul]

Hi all,

came across this. When replacing two tyes, Michelin recommends having the new tyres on the rear.

aplolgies if this has been posted before

Click on the last link and there's a video as well.

http://www.michelinman.com/tire-care...#install-tires

[spacepants_fb]

Dude, didn't even know that! Good find...does it apply for both fwd and rwd?

[beeza]

It makes sense...

[destrukshn]

lol, yeah, but what if you understeeer?

[beeza]

Hehe exactly,hello tree...
Need to replace all 4

[VL_Commy]

that applies to RWD cars. FWD should always do the front.

[rahul]

that applies to RWD cars. FWD should always do the front.

that's what i thought.. the video is a bit ambigious whether it applies to FWD or RWD. It shows a cd5 at the start, then a 3 series and not sure if the test cars are FWD or RWD.

[JohnL]

They're assuming more grip from the new tyres, and recommending fitting the new tyres to the rear so as to avoid any tendency toward increased oversteer. This is the case for front or rear wheel drive, or four wheel drive for that matter.

It's assumed by car and tyre manufacturers that the average driver is likely to die in the event of oversteer because oversteer typically requires a higher level of skill to deal with appropriately than understeer. This is why car manufacturers go to great pains to ensure that 99% of their products are strong understeerers. The tyre manufacturer will give this advice with a driver of average skill (or lack therof) in mind, for the same reasons as the car manufacturers design their cars to understeer.

If you would prefer less understeer and are realistic about your skill levels then you could fit the new tyres to the front, keeping in mind that if you have an accident due to oversteer then it's your fault. While (all else being equal) the new tyres will tend to give more grip and more grip in the front if fitted on the front, they will tend to have less steering response, at least until the tread blocks have worn down to some degree.

When I was lot younger and used to drive way too fast, I had a flat rear tyre which I then replaced with the (new) spare. I then proceeded to continue my too fast fang along my favourite 'track', until I came to a very fast corner that I took as fast as I usually did, resulting in a very scary rear end slide that saw the car at a big angle to direction of travel for a very long distance. I was so lucky that I didn't spin it or hit any of the cars parked on the road side (I'd like to think skillful, but lucky is more accurate!). The cause? Apart form stupidity, it was the mould release agent on the new rubber. Brand new (like really new) tyres have very poor grip until this is scrubbed off.

[jdm_kid]

which cheapo would buy 2 tyres lol unless its semi slicks haha

[beeza]

I did.I skided too hard a few times on the front.Wore flat patches on my Nankangs.

[JohnL]

which cheapo would buy 2 tyres lol unless its semi slicks haha

Lots of people, many much less cheap than I am!

Front tyres wear about twice as fast as rears, I'm not throwing perfectly usable rubber away, are you mad?!

Anyway, what difference does it make if the tyres are semi slicks? If the tyres are for racing purposes (or even merely 'high performance' road use) you could make an argument that only replacing two semi slicks is sillier than replacing only two more ordinary road tyres.

Keeping in mind that racing rubber deteriorates significantly with every heat cycle the tyre is subjected to; Say you start off with a set of 4 new semi slicks and then wear the fronts out racing (or just hooning around like a maniac). You then buy only two new for the front, so now have new front tyres with good grip, but two old rear tyres that have seen quite a few heat cycles and are therefore not as soft and sticky as they once were.

You now have a mismatched set of tyres with poorer performing tyres on the rear. I'll bet the handling and grip balance is now worse than with the original 4 new tyres, and that lap times go up, unless that is the basic set up is unbalanced with too much understeer, but now more balanced with crap rear tyres.

[panda[cRx]]

all mechanics and tyre specialist i know put them to the front. they do all your steering and your fronts cover most of the braking (and for fwd all of the acceleration too)