New profile on stock tires

Discussion in 'General Chat' started by opboy, Sep 22, 2012.

  1. opboy

    opboy Copenworld Newbie

    Joined:
    Sep 3, 2012
    Hi all, would like to know if it is possible to put 175/50/15 on our stock rim which is 165/50/15? Or what is the max size it can go without compomise safety.
     
  2. terry urwin

    terry urwin Copenworld Newbie

    Joined:
    Jul 27, 2012
    Location:
    consett
    Car(s):
    yes vivid
    hi the 185 are only 5mm each side bigger no probs fitting just better grip i am running 195/45/15 but on bigger rims thay stick out a bit but look ace hope this helps...
     
  3. opboy

    opboy Copenworld Newbie

    Joined:
    Sep 3, 2012
    Thanks, was thinking of getting broader tires as more choices
     
  4. Binz

    Binz Copenworld Regular

    Joined:
    Apr 27, 2012
    Location:
    North Hampshire
    Car(s):
    Copen (plus Kawasaki W650 and Honda CRV)
  5. Rex

    Rex Copenworld Pioneer

    Joined:
    Oct 20, 2009
    Location:
    Cardiff
    Car(s):
    Copen
    As all speedo's under read these days, it will probably be more accurate!
    Rex
     
    Last edited: Sep 30, 2012
  6. opboy

    opboy Copenworld Newbie

    Joined:
    Sep 3, 2012
    Hi Binz,

    thanks for the info :)
     
  7. Gimli

    Gimli Copenworld Newbie

    Joined:
    Dec 22, 2012
    In the UK don´t you have any problems by changing the tire size, for instance with the police or MOT?


    I´m from Portugal and if i change the tires on my car to a size that isn´t on the car specs I get a ticket.
     
  8. Adam K

    Adam K Copenworld Guru

    Joined:
    Oct 27, 2010
    Location:
    Worcester, UK
    Car(s):
    Nissan Cube Kaizen
    No we don't have any trouble in the UK.
     
  9. trustafox

    trustafox Copenworld Guru

    Joined:
    Nov 19, 2012
    Location:
    East Mids
    Car(s):
    Yes
    The difference wouldn't be anywhere near 10% unless you made a seriously different change.
    Going to 175/50 is only 1.8% so only just over 1 mph extra at 70. If you refer to my satnav speed comparison thread at 70 the speedo is 5 mph out, so it would chnage to 4 mph. A 185/50 is only 2.5 mpg more at 70 mph. But I read the max recommended for a 4.5J is 175.

    Love all these numbers! :)
     
  10. Quartz

    Quartz Copenworld Regular

    Joined:
    Nov 7, 2012
    Location:
    Durham
    Car(s):
    Grey Copen 2007
    I'm running on standard alloys a set of Kumo 175/50/15. Much softer ride and better in the wet, also they are cheaper than the recommended Bridgestones.
     
    Last edited: Jan 1, 2013
  11. Gimli

    Gimli Copenworld Newbie

    Joined:
    Dec 22, 2012
    Now that´s odd!! ;)
     
  12. trustafox

    trustafox Copenworld Guru

    Joined:
    Nov 19, 2012
    Location:
    East Mids
    Car(s):
    Yes
    have you ran on standard sized tyres then?
    I'm wondering if you noticed a reduction in acceleration and/or low revs at a given speed with the 175/55? those give you 5% longer travel per rotation
     
  13. Quartz

    Quartz Copenworld Regular

    Joined:
    Nov 7, 2012
    Location:
    Durham
    Car(s):
    Grey Copen 2007
    Ran it on the standard Bridgestones for about a month. I didn't really notice a reduction in acceleration. But the grip is much better in the wet when pulling away and when hitting surface water. Although the tires I have on now you can't corner them as hard as the originals. The originals being like elastic bands in comparison! :)

    As for fitting I had them done by http://www.etyres.co.uk, the guy who fitted them said that he only JUST managed to get them on!


    Sorry got the wrong tyre size there

    175/50/15/H KUMHO KH17

    Fitting and disposal for all 4 tyres £267.98.

    Kwik fit was going to be around £300 and i'd have to drive it in and wait 3 hours...
     
    Last edited: Dec 31, 2012
  14. trustafox

    trustafox Copenworld Guru

    Joined:
    Nov 19, 2012
    Location:
    East Mids
    Car(s):
    Yes
    Who you mean only just got them on? is that standard rims and being only 4.5J the 175s were almost too wide?

    Why don't they corner as well, what happens? it rolls a lot more or not got the grip.
     
  15. Quartz

    Quartz Copenworld Regular

    Joined:
    Nov 7, 2012
    Location:
    Durham
    Car(s):
    Grey Copen 2007
    They are a little wider than the standard 165. The guy from etyres was a little concerned about them not being the same as the originals that's all. I have had no problems with them...apart from the fact I corner too hard sometimes ;)

    The pros (+) and cons (-) of both tyres are:

    Bridgestone standard tyres (165/50R15 73V)

    + Better at cornering.

    + Reinforced tyre wall.

    + Standard fit.

    -------------------------------------------------------------------------------------
    - Poor scores in new EU tyre testing brought into effect last year.
    (A-G scale, G the worst)

    C in the wet,
    G for fuel consumption.

    - Expect to pay more than (possibly) better alternative tyres.

    - Can easily spin in the wet under moderate to hard take off.

    - Can be a rough ride on UK roads!
    _________________________________________________________________

    The current tryes I have fitted:

    (175/50/15/75H KUMHO KH17) example here... http://www.tyrewizard.co.uk/car-tyres-c4/15-c8/kumho-solus-kh17-175-50-r15-75h-tyre-p1203

    + Softer ride.

    + Better wet grip and reduced wheel spin.

    + Marginally cheaper than recommended.

    + Better EU score
    B in wet,
    E for fuel consumption.

    --------------------------------------------------------------------------

    - Not as good for cornering.

    - The drive is a little dulled down.

    - You'll rub the walls of the tyre and (thankfully) not your alloy when you park it!

    This of course is from limited personal experience as I have only owned the car for about 2 months. When choosing a tyre try to go for the best scoring cheapest tyre you can find. If you're not sure then just stick with what you have.

    Oh and aviod the tyre make called MULTISTRADA - ATR K-ECONOMIST.
    they are low budget with VERY POOR scores!

    (Sorry for the really long post) :)

    PS

    The new tyres actually make the car roll a little in hard cornering where as the originals the car just moves sideways! ;)
     
    Last edited: Jan 1, 2013
  16. trustafox

    trustafox Copenworld Guru

    Joined:
    Nov 19, 2012
    Location:
    East Mids
    Car(s):
    Yes
    what pressures are you running them?

    I wondered if standard copen pressures or do the tyres come with their own recommended pressure? If standard copen pressures, could that be a bit low for the Kumho's if the Bridgestone's have reinforced walls that means its self supporting and doesn't need such a high pressure? Then the Kumhos could be a bit soft.
     
  17. Quartz

    Quartz Copenworld Regular

    Joined:
    Nov 7, 2012
    Location:
    Durham
    Car(s):
    Grey Copen 2007
    The Kumho's are set at 35 psi (as per originals). This seems enough, but due to lack of data it could be an incorrect figure. This was pre set by etyres who were probably following manufacture guidelines (if such exist for this tyre type on this car).

    Etyres guide: http://www.etyres.co.uk/tyres/daihatsu/
     
    Last edited: Jan 1, 2013
  18. Quartz

    Quartz Copenworld Regular

    Joined:
    Nov 7, 2012
    Location:
    Durham
    Car(s):
    Grey Copen 2007
    After checking the manual (34.8 psi for originals) there is virtually no data on the tyre pressure for the type I have fitted. The only way to see if it is really inflated correctly is by sitting the car on a flat surface and see if the contact to surface is correct and not over or under inflated. Bugger me, as they are slightly bigger I think i'll go 36 psi ;)

    I have just found that the max pressure for the tyre is 44 psi: http://www.camskill.co.uk/m53b0s113...o_KH17_Solus_Kumho_KH_17_-_175_50_R15_75H_TL_

    imagine running them at 40 psi...that'll be interesting and will have to try it...hmmz.
     
    Last edited: Jan 1, 2013
  19. trustafox

    trustafox Copenworld Guru

    Joined:
    Nov 19, 2012
    Location:
    East Mids
    Car(s):
    Yes
    Well that is some info to give you a top line, but I was thinking maybe a psi higher, like you say 36.

    You need a standard tyre and put a weight on it and measure its height. Then do the same with your tyre, same weight and adjust pressure until it gives the same height reading to equate same load on the tyre.
     
  20. Quartz

    Quartz Copenworld Regular

    Joined:
    Nov 7, 2012
    Location:
    Durham
    Car(s):
    Grey Copen 2007
    Been promoted :)

    True, 36 psi seems realistic. Now I just have to fit my RamAir induction kit replacing the old K&N 57i used for test purposes and then actually finish off that thread about UK remap for the 1.3 (or see a load of long faces) when I next get paid...

    36 psi didn't seem enough. Just done 38 psi today and the tyre action is similar to the original bridgestones. So I suspect this pressure level is near right.
     
    Last edited: Jan 2, 2013

Share This Page