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Tyre Pressures

Discussion in 'Bling and Appearance' started by flexorcist, Sep 21, 2006.

  1. What should the tyre pressures be on my 94 zzr 250?? also is there a sort of "standard" pressure that applies to bikes of diff sizes

  2. I keep my rear at 36 and my front at 34, make sure you check the tyre wall, it should be written on that.
  3. depends a bit on tyre type, weight of rider etc. i run the VFR ones at 34
  4. I was of the opinion tyre pressures were meant to be checked and filled when cold? Otherwise you get a hike of 5 or so PSI (and more depending on how warm they are). Might be wrong but was always told to check them when they are cold............????
  5. Yep checked cold
  6. Hmmm, maybe I should ring the tyre guy and ask him, my informant may have got it wrong, wouldn't be the first time.
  7. 5psi higher than factory recommends is a good start!
    I run the GTR at 41 f/ 38r. I ran the Z650 at around the same pressures.

    Regards, Andrew.
  8. Heat changes the pressure so you can't correctly measure psi if your tyres are not a standard (cold) temperature. At rider training they gave us examples of where adjusting tyre pressure different to factory spces would be favourable. EG: Long distance, rain, pillion, ambient temperature.
  9. hmmm this is something ive been wondering about too. one thing i noticed fr the VTR at least too is always have the rear at a slightly higher pressure than the front. im not trying to condradict you typhoon, you know far more about it than i do. it just seem sharper this way for me. i also run pretty soft tyres, (compared to my old ones at least) pirelli sports demon, when i have a higher pressure ie 40F/42R (maximum recommended and what works best in my car) i find the handeling much sharper and firmer in corners, however at the expense of traction when on a sharpe lean. especially if i give it any throttle, in which case it doesnt take to much to convince it to start sliding out. i rekon ll play around with it so its the midway between maximum and honda recommended. try and find the right balance
  10. 38f 40r on the beemer
    On the smaller 250's 34f 36 rear seems to be the standard.
  11. Don't worry about contradicting me, my example was for my bike only. The GTR is not a typical "modern" motorbike in that it has a pretty small front tyre and is very heavy, so needs more air pressure to help prevent cupping of tyres.
    Your tyre pressures work fine for you and your bike, which is cool.
    I duno if I know far more about it than you either!

    Regards, Andrew.
  12. Michelin Pilots -
    Rear 180/17/40 - 38-40psi
    Front 120/17/60 34-36psi

    I havnt pumped them up for a good 2 months and when i did, you can instantly feel the difference. Always good to check them once a week.
  13. air pressure should be written on your bike or in the user manual
  14. Yep, as long as you have original tyres.

    The recommended pressures should be on the tyrewall.
  15. for low speed highchair wheelies, I suggest 10 psi in the rear
  16. Not trying to hijack here... but are the ZZR250 and the ZXR250 have the same tyre size?

    I couldn't find anything on the bike and the manual. I look at the typres... but don't know what to look for..
    What pressure should I put onto the ZXR250?
  17. Tyre pressure should be somewhere on your bike frame (NOT the tyre wall), it may be in kpa rather than psi. I think 28psi for front and 32psi for rear and its best to stick with the bike manufacturers guidelines not what is on the tyre wall.

    For example, my bike has a whole heap japanese words then 200kpa and 225kpa on the plastic cover above the chain - and the words and numbers are very tiny.
  18. This is what i think, its not gospel so by all means beleive what you want
    if you have crossply tyres i would be running 34front/36rear, most small bikes run these tyres, just check the sidewall they should have a C somewhere
    if you are running radials 36front38rear, or if your running radials and you have a heavy bike or frequently ride with a pillion run 38front/40rear.
    all these are cold pressures btw.

    I personally dont think there is any problem checking your pressures when your tyres are hot, as long as you are consistant and you figure out what hot pressure is the same as the cold pressure that you are aiming for. I find it more conveniant to check them hot because its not very often that i arive at a servo with cold tyres. Just set your pressures cold, go for a ride to warm them up and then check them again and write down or remember what pressure they should have in them when they are hot.
    not too hard.
  19. I actually talked to someone yesterday who ran 40,42 in his vfr800
    he said at lower pressures the bike is squirmy, I was thinking of giving it a go as my bike is squirmy in corners .. any thoughts??
  20. It can't hurt. What does the Z weigh? As I said above, I run those pressures in my behemoth. If you don't like how it handles, change back.
    The only thing to watch with increased pressures in any tyre is it will probably have slightly more grip, but will break free a bit faster with more pressure. That's a bit of a generalisatin, but it's usualy the case.
    The bike manufacturers don't just consider tyre grip whensuggesting tyre pressures, they consider tyre life and ride quality. And don't forget the tyre recommendation by the manufacturer was for the OEM tyres...
    Radial tyres tend to benefit more from increases in pressure, crossply tyres just tend to distort the tread and bulge in the centre. Radials have softer sidewalls compared to crossplys, which are stiffer in the sidewalls, due to the way the tyres are constructed.

    Regards, Andrew.