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hi there i am a tyre fitter and a strong believer in not having low profile tyres on any car they make look nice but as you have already pointed out they change the drive of the car. tyres are also cheaper in the none low profiles so i would recommend to get them changed just make sure the size tyre on the ones dealer offer you are the correct size... u can do this quickly and easily by going on kwikfits web site and putting in your reg number and it tells you what size should be fitted to your car.. as for benifits towing wouldnt know as i have a 4by so doesnt affect my tractoe tyres hope this was of help

Quote: Originally posted by LegsDownKettleOn on 24/8/2008The reason a wider tyre aquaplanes is that they still have the same escape zones for the water around the sides of the tyre, but being wider they are displacing a lot more water which means it is harder for the displaced water to escape through the grooves in the tyre increasing the liklihood of aquaplaning.

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I'm sure thats incorrect, a given width of tyre/wheel combo places the same footprint onto the road whatever its profile.

Where the profile changes things is that with a 45 for example theres less sidewall flexing than on a 75. Less give in the tyre makes for tighter handling and more stability but less softening of the ride for passenger comfort. A 6'' wide rim when its not under duress will always place 6'' (or thereabouts) worth of tread down onto the road whatever its profile.

As far as perception of grip goes I think your getting confused with the fact that wider tyres in general use these days do give much better grip than ever before in the dry but the down side of the increased width is the snowshoe effect. Where a pram wheel width tyre would cut throught the snow or water , a conventional tread on a wider tyre may not and just sit on it. Thats one reason we're seeing more directional treads and those that look like several different treads on one tyre as opposed to the old fashioned block style of years ago and the tread min was changed years ago from 1 to 1.6 mm (and should be reviewed again).






Post last edited on 24/08/2008 11:49:26

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davedy@nyms.net

Personally I'm not a fan of low profile tyres, whether towing or not.

I know of one instance where an accident occurred because of the tyres - an ex-pupil of mine swerved to avoid a dog on a fast moving road and went over the edge of the tarmac on to the stones. With conventional tyres he would have been able to steer back on to the carriageway but because of the low profile tyres he had fitted to the car he wasn't able to get back up out of the stones and onto the carriageway.

I'm sure they're fine on nice smooth tarmac, but with the state of some of our motorways where the inside lane particularly has deep ruts, I feel they could create a hazard.

Quote: Originally posted by daved on 24/8/2008

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Quote: Originally posted by LegsDownKettleOn on 24/8/2008The reason a wider tyre aquaplanes is that they still have the same escape zones for the water around the sides of the tyre, but being wider they are displacing a lot more water which means it is harder for the displaced water to escape through the grooves in the tyre increasing the liklihood of aquaplaning.

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I'm sure thats incorrect, a given width of tyre/wheel combo places the same footprint onto the road whatever its profile.

Where the profile changes things is that with a 45 for example theres less sidewall flexing than on a 75. Less give in the tyre makes for tighter handling and more stability but less softening of the ride for passenger comfort. A 6'' wide rim when its not under duress will always place 6'' (or thereabouts) worth of tread down onto the road whatever its profile.

As far as perception of grip goes I think your getting confused with the fact that wider tyres in general use these days do give much better grip than ever before in the dry but the down side of the increased width is the snowshoe effect. Where a pram wheel width tyre would cut throught the snow or water , a conventional tread on a wider tyre may not and just sit on it. Thats one reason we're seeing more directional treads and those that look like several different treads on one tyre as opposed to the old fashioned block style of years ago and the tread min was changed years ago from 1 to 1.6 mm (and should be reviewed again).






Post last edited on 24/08/2008 11:49:26

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Technically that is correct, but what happens is that a standard tyre of for arguments sake 155/80/13 would have a low profile tyre reeplacement on the same wheel of around 165/70/13. In order to get the same radius of the wheel and therefore preserve speedometer accuracy and ground clearance, then the tyre radius must be preserved.

More often than not, when a low profile tyre is fitted it is accompanied with a different wider and larger wheel, so the aforementioned example might even be replaced with a tyre in the region of 205/50/14

The op suggested that it is just a case of swapping the tyres so I assume that the wheels are the same. However the price of £140 to swap 4 tyres over is through the roof when you consider that you can buy 4 cheap tyres and have them fitted for £99. OK, the tyres are dearer, but changing a tyre is no more labour intensive on an expensive tyre than it is on a cheap one.

What's more, if the wheels are the same, I but they just swap the wheels over.