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View Full Version : Changing to non-runflats: what load rating did you go for?



a11y
21st December 2016, 11:02 PM
My current RFTs are 205/45/17 84 V (2 x Bridgestones, 2 x Dunlops).

What load rating have folk gone to when changing to non-RFTs?

I'm pretty much set on Uniroyal Rainsport 3s in 215/45/17 (yes marginally bigger diameter but within recommendations and should 'correct' the speedo accuracy - this thread on PH (http://www.pistonheads.com/gassing/topic.asp?t=1423732) helped me decide..). Loved the Rainsport 2s on a previous hot hatch and they're only £55 each online at the moment. Person in that thread went for 91Y XLs.

I can get the Uniroyals in 87Y or 91Y XL. Swinging towards the 91Y XL to compensate slightly for the move to softer sidewalls on non-RFTs (which should in theory retain decent turn-in), but don't want to end up with a tyre with a similar stiff ride to the RFTs so maybe the 87Y is a better bet? The Uniroyals also have a reputation for having soft sidewalls so again that's me back to the 91Y XLs. And round I go again :confused:

I know some people get on with them but I really didn't like how the felt on the car. Having swapped from RFTs to normal tyres on my previous 2 cars (both BMWs) I know the change they can make.

Cheers,
Ally

Dobboy
21st December 2016, 11:34 PM
Where are you getting them for £55?


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CiderFex
22nd December 2016, 03:49 AM
My KU39's are 215/45ZR17 91Y.
I personally have never had any issues with them no matter what I throw their way.
They do slightly catch the wheel arch trim occasionally, the GP is 30mm lower though, but that's usually when on The HBT's which cant really be classed as "normal" driving.
[emoji23]
They are 4% out from standard so for every 1000 miles I drive my odometer only reads 960.
[emoji15]
(The above has been worked out using GPS miles versus indicated miles)


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a11y
22nd December 2016, 08:57 AM
Where are you getting them for £55?

Camskill - linky (http://www.camskill.co.uk/m54b0s15p111647/Uniroyal_Tyres_Car_Uniroyal_RainSport3_Uniroyal_Ra in_Sport_3_-_215_45_R17_91Y_XL_FR_TL_Fuel_Eff_%3A_C_Wet_Grip%3 A_A_NoiseClass%3A_2_Noise%3A_72dB), although I just noticed there's £13 postage on top of that. And of course that excludes fitting. Blackcircles, mytyres, Oponeo are all more expensive although prices fluctuate daily.

The KU39's (http://www.camskill.co.uk/m54b0s15p128644/Kumho_Tyres_Car_Kumho_KU39_Ecsta_LE_Sport_Kumho_KU _39_-_215_45_R17_91Y_XL_TL_Fuel_Eff_%3A_C_Wet_Grip%3A_A _NoiseClass%3A_3_Noise%3A_74dB) are identical price, I've considered them too after recommendations on here.

There's only 1.46% difference between 205/45/17 and 215/45/17 I thought. Would mean when speedo's reading 70mph the actual speed will be 71.02mph, i.e. cancel out the standard under-reading a wee bit.

From: http://www.miatatirecalculator.org
Original tyre New tyre
205/45 R17 215/45 R17
Radius, mm 308.15 312.65
Circumference, mm 1936.16 1964.44
Circumference difference, mm 28.28
Circumference difference, % 1.46
Vehicle speed as speedometer reading is:*
50 km/h 50 50.73
80 km/h 80 81.17
100 km/h 100 101.46
120 km/h 120 121.75
* Note: it is assumed that speedometer shows real speed with original tires.

(although that's me assuming you were originally on 205/45/17 CiderFex!)

- - - Updated - - -

Oh, and thanks - I'll go for 91Y I think.

Dobboy
22nd December 2016, 02:42 PM
Thanks, I'm looking for a pair for my 2nd mini, seems a good shout.

Willtheyfit.com is a good site for checking tyres/wheel offsets etc if you haven't seen it.


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CiderFex
22nd December 2016, 09:11 PM
I can't remember the original size of the GP tyres but they were on 18x7 wheels.
No doubt an ex GP1 one owner, there are loads in NMS, will pop along with the OEM tyre size that I originally had.
My speedo reads 73mph when I'm actually doing 70mph on the GPS.


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Mon the fish
22nd December 2016, 10:10 PM
I can't remember the original size of the GP tyres but they were on 18x7 wheels.
No doubt an ex GP1 one owner, there are loads in NMS, will pop along with the OEM tyre size that I originally had.
My speedo reads 73mph when I'm actually doing 70mph on the GPS.


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205/40 R18.

And I've never owned a GP [emoji6]

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CiderFex
22nd December 2016, 10:18 PM
Thank you.
[emoji1303]


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a11y
23rd December 2016, 11:10 AM
Checked with insurance about changing to non-RFTs - all good. Tyres getting ordered once I've settled on somewhere to have them fitted (and have, I'm ashamed to admit owning one, decided on caravan tyres to include in my order :p)


And just realised when I meant 'under-reading' in earlier posts, I actually meant over-reading, i.e. as standard all speedos over-read but fitting slightly bigger diameter wheels/tyres brings it more in line with actual/GPS speed.

- - - Updated - - -

Ordered :)

(SOS Motorsport in Falkirk - just off Grahams Rd next to canal - quoting a tenner a wheel for fitting)