How bad is it to put smaller tyres on ?

Zenith63

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Not a major problem at all. Your speedometer will be a little less accurate, but it was unlikely to have been accurate to start with. The ride will be ever so slightly harsher. You’ll be a little more prone to rim damage due to less tyrewall to protect from potholes. Have done it many times...
 

Leo

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~9% difference in sidewall will affect handling a little, ~3% difference in circumference unlikely to be a big deal for speedo / gearing ratios.
 

mathepac

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Modifying tyres and or wheels from the manufacturer's specifications may affect your insurance. Approved specifications and pressures are marked on the vehicle, usually on the B-pillar or inside the fuel-filler flap. Check with your insurer (not the broker) before you make any changes.
 

Bronte

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We were on our summer holidays a couple of years ago and had to put the smaller spare wheel on. The repair company man told us we had to drive at only 80 KM an hour max and that the tyre shouldn't be used for too long as it overheats. It is no joke trying to do only 80KM an hour on motorways and having to pull in to let the tyre cool down. I can't see how it would be a good idea to use tyres that are not the normal size for your car. Why would you want to do that?
 

Bronte

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Completely different thing.
Okey dokey. I'm not a car person so I haven't a clue about tyres. But I'd still think you shouldn't be putting smaller tyres than what the manufacturers recommend.

Edit: The OP might want to have a bit of a read of this, and the trouble not putting on the right tyres, it's not exactly the same but the OP can get the gist.

 

AlbacoreA

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Thats about substandard tyres (and of the right size anyway). So again completely different.
 

Páid

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My old Toyota has 205 60 R16's.

How bad is it to replace them with a set of 205 55 R16' ?
Why would you want to do this? To save money?

One thing I won't compromise on is tyres. It can be the difference between avoiding an accident and having one.
 

AlbacoreA

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Why would you want to do this? To save money?

One thing I won't compromise on is tyres. It can be the difference between avoiding an accident and having one.
Maybe I'm misisng something but what has that got to do with the profile?

In theory all else being the same (same model tyre) other the the lower profile, the lower profile Tyre will have better performance than the bigger one.
But its probably the difference will be minimal in this case. It will just be a slightly harsher ride.
 
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Daddy Ireland

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Thanks for furthere replies. I was just wondering is there much of a difference in changing tyres currently from 205 60 R16 to 205 55 R16. Not saying I would do it.
 

AlbacoreA

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Many drivers of BMWs and Audi sometimes get rid of the run flats and go to a bigger profile to try reduce the harsh ride.
 

SparkRite

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Some of the replies are somewhat OTT.

We are talking about a 5mm difference in 'ride height' of the tyre ie. sidewall.
This is less than the normal thread wear of a new tyre versus a (still legal) part worn tyre, ie. 8 - 6.4 =1.6mm.
So to the OP, no discernible difference if you were to use the lower profile tyre(s).

C'mon, get a grip (ha, see what I did there).
 
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