why does wheel diameter affect handling?

[Pep]

well.....!

just wondered, seen quite a few people say 17's arent as good as 15's but never known why

 

[Pep]

whats wrong with everyone tonight?!

 

[Macester]

Everyone has gone quiet, I still can't decide whether to get 16s or 17s, its been on my mind for days doing my head in!

 

[Pep]

id go for 16's personally, i think 17's are a bit over the top for the size of a clio, although saying that if the style is right...

 

[Brown.]

it depends on the size of tyre accompanying the rim..... if the outer diameter and width stays the same, and the rim is strong there wont be a diff, unless put on a formular one car...... 15 inch steelies flex less then 17's...... 1.2's and the like.... wheel size wont make a slight bit difference

 

[Pep]

o right, but how come with performance cars, such as a v6 they have 18's on?

is it just a balance between looks and performance?

 

[gav182]

i wouldn t put 17s on 1.2 it will raise gearing too high

 

[Jones]

its the unsprung weight not the size, the size of the wheel is canceled out by the profile of the tyre eg a 13" rim with a 60 profile tyre vs a 15" rim with a 45 profile will be near enough the diameter

 

[GordonD]

well.....!

just wondered, seen quite a few people say 17's arent as good as 15's but never known why

Bigger diameter wheels usually make the handling better because when you increase the wheel diameter you put lower profile tyres on that put more rubber on the road and have shorter more rigid sidewalls.

But bigger diameter wheels make the ride worse on rough surfaces because a larger diameter wheel is significantly heavier.

People put bigger diameter wheels on to make their car look more like a race car. But the reason race cars put bigger diameter wheels on - in classes where they're allowed to - is so they can fit bigger brakes. You'll note the rally cars, which unlike, say F1, are allowed to run bigger diameter wheels, don't, because they have to cope with rough roads.

 

[Turkish]

Weight, offset and width usually change when people up the size of the wheel which people dont account for. If you were comparing identical offset, weight and width wheels (highly unlikely) even with the same brand tyres, the amount of sidewall reduces and therefore the amount of flex in the tyre so that effects the handling/ride of the car too. I had 17s on my old 172 and when i put the OE 16s back on the car drove far better IMO. You'll find alot of other people on here who've done the same will say exactly the same thing.

 

[Bluebeard]

on this subject, my ph1 172 tramlines (not a lot mind you) now i've put turinis on it, but was fine when it had std wheels on it. Why does this happen?

 

[Turkish]

Normally tends to happen the wider the wheel/tyre you put on. Some of the Beemers I used to drive would pull all over the road when they had schnitzer rims fitted on them. Have you changed from a 195 to a 205 tyre? sometimes certain brands of tyre tend to tramline more than others brands the same size.