Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

N00b Q: What tyre pressure?

Discussion in 'Bling and Appearance' at netrider.net.au started by ~DadAgain~, Jul 2, 2008.

  1. Ok so its probably been asked before - but I did a search and didnt find anything conclusive.



    I realise tyre pressure is a fairly crucial part of my bikes handling so a couple of quiestions:

    1) How often do you check? (I'll commuting 15km each way 5 times a week - so not doing a whole lot of kms - but I still figure I should check the pressures every now and then... )

    2) What *is* the correct pressure? All I can gather from poking around on www is a front somewhere between 28 and 35psi and a rear around 32-35psi? - Anyone care to suggest any better numbers for my ZZR? Does it depend on the tyre? Is it written in an ancient mystical secret code on the tyre?

    3) Are servo forecourt airlines/guages good enough? Are there any differences? - Lots of bikers seem to stop at our local BP (The Gap, QLD) - but theres a Mobil down the road that also has air - ... could there be wide variances in accuracy of their guages? or is the difference in patronage just a bikey cultural thing?!

    4) How do you tell when a tyre is due for replacement? Is it just a tread depth thing? are there any clear indicators that its time?

    I dont think I have a tyre problem - but I'm keen to make sure that I'm on top of tyre maintenance before I learn the hard way that I dont have enough grip!
     
     Top
  2. Buy yourself a reasonable quality tyre guage and take a reading, then go to several garages and see whose pressure lines come closest. Use the closest one!
     
     Top
  3. 1. Check once a week until you know how long it takes for your tyres
    to lose air, then you might ease back to only once a month unless the
    handling feels wierd (sign of low pressure).

    2. ZZR official pressure is 28 front, 32 rear. unless carrying heavy load.
    Most ZZR riders usually prefer about 32 fr, 34 rear which lightens the
    steering and makes it more responsive, but a little easier to skid or slip
    the tyres especially when cold/wet. If in doubt use official pressure.

    3. No, servo gauges are often complete sh**. Buy a good gauge (not
    just a $8 one) and do like Hornet says.

    4. Tread depth is an obvious and easily checked sign.
    Also replace your tyres :
    - if they get old enough to get cracks in the sidewall or tread
    or
    - if they wear a funny shape and make the bike steer wierd
    (e.g. not want to turn into corners, or the steering shakes a lot, etc)
    or
    - if they are older than a couple of years and start to go hard and
    lose traction (An official communique from a brand I can't name
    says Shelf life with waxy coating on is 6years, once installed
    and used first time and the waxy coating rubs off, only 2 years).
    or
    - if you have not got confidence in them. You need to ride
    in confidence that you can use your brakes properly and your tyres
    will cope, you can swerve when you need to and your tyres will cope.
    Otherwise you will not swerve or brake enough in an emergency.
    This is where deserted carparks make good practice/test areas
    so you can slowly develop your skills in emergency swerve and brake,
    this will also demonstrate to you that your tyres will work (or if they
    don't, you will be able to let off the brakes or swerve without crashing
    and then you can go buy new tyres).
     
     Top
  4. What Hotcam said.

    Plus:
    I check weekly at the forecourt and have a digital gauge at home. They're never more than +-2% different. Nobody checks pressures daily unless it’s on a pre-start checklist for a work bike.
    Don't forget to check your tyres when they're cold.
    There might be a sticker on your swinging arm showing the pressures. You might find different ranges for your bike depending upon if you've got a pillion or carrying heavy luggage etc.
    These days you can even get on-bike pressure measuring tools. Check out http://safetysolutions.com.au/joomla/ if it tickles your fancy, and you’ve got a hole in your pocket. :)

    This is an interesting, though biased (no pun intended) link for Michelin tyres. http://two-wheels.michelin.com/2w/front/affich.jsp?codeRubrique=2092004103637&lang=EN
     
     Top
  5. I'd rather the MObil for Fuel and the BP for air :p

    the BP one is electronic, you punch in the no. and shove in the air thingiemabobby lol
     
     Top
  6. I got a small air compressor in the car that runs off the ciggie socket. Its got a digital gauge and you can tell it to pump to a specific pressure.
     
     Top
  7. Your manual will list tyre pressure for you. You should also find a sticker near the rear will with that information, usually on the swingarm or chain gaurd.

    For improved responsivness most people +3-4 on what the manual says. This will mean a small loss of tyre footprint but the difference in traction should be insignificant.

    Most servos these days have digital pumps which are fairly good. I've never had one of these new gauges argue with my hand held gauge. The older style servo gauges should be avoided though. :)
     
     Top
  8. Yeah... any idea where I get one of them? I got my bike 'as is' - good tidy looking machine but nothing besides the legal minimum of paperwork and the key!

    I guess I should get it serviced since I dont know how long its been since it last saw a mechanic! :?
     
     Top
  9. I have a small foot pump at home and a gauge. I only ride weekends so check the night before and I often just need a pump or two with the foot pump. From home is best as your consistently measuring a cold tire.

    It does not hurt to fiddle around with the pressures a bit - you can easily go up and down a few psi from recommended just to see if you can feel the difference. Track bikes use much lower pressures to get a bigger contact patch on the road - but not recommended on the "real" roads as potholes will damage your rims if you get too low.

    If you go a bit lower - it will feel squirmy at first and take a bit longer for the tires to warm up.

    Tire wear - the back usually goes flat in the middle first so is easy to tell. If you regularly go us Mt Glorious, the front will wear on the sides which is more difficult to tell. A good front is a round front, once it starts to get a wedge shape, it feels like it is "dropping" into corners more than it should. Once you get new tires its easy to tell the old were cactus as the new feel so much better! Also replace if the tires are getting real old and start to go hard.
     
     Top
  10.  Top
  11. I got nitrogen in my tyres - cost $15 from Bob Jane and I get it checked every 2-3 months (costs nothing). Front 28 and rear 32 psi. Haven't had a change in psi for over 5 months
     
     Top
  12. hey cozican... what are the advantages of using nitrogen?
     
     Top
  13. Less air leakage so your psi is constant, longer lasting tyres - if its god enough for Casey, its good enough for me!

    Husband has been getting the tyres nitro filled for about 6 years, never had a problem with it.
     
     Top
  14. Its something about Nitrogen particals are bigger than "air" so it leaks less. I've also read that as it is all N2, its performs better when heated/cooled compared to "air" which is a mixture of many gasses. Could be true I guess?

    I don't mind "regularly checking" my tire pressure - its a good excuse to take a quick look around the bike for any problems before a ride anyway.
     
     Top
  15. yeah i will normally check mine twice a week, only for the fact during the week they go up in pressure (to try and keep them from squaring off) during my weekly commutes, and come friday night/saturday morning, i drop them again for weekend fun times, when i prefer them a little softer :wink:
     
     Top
  16. Have you looked under the seat?

    Otherwise, try google. :)
     
     Top
  17. Just make sure you ask for nitrogen & not helium ....

    Sorry .... I'll go now ... :wink:
     
     Top
  18.  
     Top
  19. Hahah, it made me laugh.

    Whoever said about the nitrogen performing better when the tyres expand and contract and go from hot to cold and back again etc is correct.
     
     Top
  20. Fill your tires with hydrogen, i hear it makes for some sick burnouts.
     
     Top