Time For New Tyres

[IQ Old git]

Hi Guys. The time has come for a set of new tyres. My dilemma is what to go for. I dont much fancy another set of Bridgestones which means going up a size. Do I go for 185x55x16 instead of 175x60x16 which will give marginally lower gearing (19.6 mph at indicated 20) which may improve the driveability due to marginally lower gearing, or 195x55x16 which has a huge range of makes including the much lauded Dunlop sport bluresponce or the new Michelin cross climate which also reads very well. My main requirement is quiet running and economy. Will 195's be too wide for the wheels ?? Any feedback will be welcome. Cheers Colin

[FROSTYBALLS]

I would use a tyre size calculator to establish any change in speedometer reading (it is illegal for a speedometer to under-read), such as - http://www.alloywheels.com/tyre-calculator

[IQ Old git]

Thanks Frosty. Have already checked them out which is where I got the mph reading from. Apparently you are allowed up to 2.5% 'error' when changing tyre size. These are both within .9% 195's give 20.1 at 20mph. My only worry is that 195's will affect the steering feel making it heavier and 'woolly' Cheers Colin

[FROSTYBALLS]

UK legislation is slightly different to EU legislation and states:

The speedometer must never show less than the actual speed.

The speedometer must not exceed 110% of the actual speed, except for speeds between 30mph and 70mph, where the indicated speed must not exceed 110% of the actual speed plus 6.25mph.

So for a vehicle actually travelling at 80mph, the indicated speed must not show more than 88mph, and for a vehicle actually travelling at 50mph, the speedometer must not show more than 61.25mph.

[IQ Old git]

Thanks again. I think that 185's and 195's both come well within the regulations. I was hoping to get feedback from someone who had fitted either of these and especially a recommendation as to what brand to go for. Looks like I will have to go for new tyres within the next week or so as one is down to the warning block on the outside edge. The tyres all appear to be original and it has now done 57k so not too bad. Cheers Colin

[alan333]

The 185 or 195 refers to the tread width in millimetres and has nothing to do with rolling circumference and therefore speedo readings. The bit that matters is the next number, which is the tyre height, as a percentage of the first number. So a 185/55 is 55% of 185mm, ie 101.75mm high. Or a 195/55 would be 107.25mm.

The warning blocks tend to be about 3mm, and the legal limit is 1.6mm tread on 75% of the tyre, and tread visible on the "bald" bits. Therefore your tyres are still legal for a while yet, but obviously are getting towards the end of their life.

[tarquin]

You can get a 215 on an iQ

David

[Tohta]

So what do folks recommend as the quietest tyres for a base model iQ? Cost?

[mhc]

I've used Oponeo a couple of times and they've always been really good on service and price, lots of tyre options too, only problem is you then have to get them fitted.

HTH

[iQ-Chris]

If it helps, I replaced mine 6 months ago for Toyo Proxes.

Chris

iQ² in black ☆ red and white leather ☆ sunroof ☆ upgraded interior lighting ☆ white backlit dashboard/switches ☆ auto-folding mirrors ☆ smart entry ☆ auto-locking doors ☆ chrome handles and exhaust

[atkiman]

I'm on nexian eco blues, good tyre, 40 quid each, big saving ovrr bridgestones .

[IQ Old git]

Thanks Guys. Have gone for 185 55's unfortunately they could only get Bridgestone turunza so I just had the fronts replaced. Nightmare, consumption gone from showing 55ish to 51 max. Have yet to do a fuelly on this tank but its not looking good. Spoke to an 'expert' who said that the Iq is designed to run on eco tyres and should always be fitted with same. Will take a copy of report to HiQ when I go back next week to have the tracking done. (foc I hope) Not a happy bunny. Cheers. Yours disgruntled Colin

[craggle]

Not surprising really with a wider tyre. I run 205 wide tyres in the summer and I'm always about 5-8mpg less than with the skinny winter tyres fitted.

Have you checked the pressure? They may have just inflated them to a nominal figure rather than what is stated in the manual.

Craig.

[tarquin]

I run 215 x18 and am down to 42 with an Auto

David