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fitting wider tires

Discussion in 'Bling and Appearance' started by mattt, Oct 21, 2005.

  1. hi i am after my first bike and have plans for some minor modifications in the future. One thing i am particularly interested in doing would be fitting wider tyres on a bike.
    Is this simply a matter of changing tyres or is changing wheels possible to accomodate even wider tyre size? thanks!

  2. ooooo eck, it's a LOT different from doing the same thing on a car, and, bearing in mind you've only got TWO tyres on the road, and not four, it's not usually recommended.

    If you want to trick up a bike for looks, there's heaps of things that you can do, but the manufacturers have a pretty good handle on how much rubber they need, and I'd be leaving that alone.
  3. It's hard to say when you don't even know what bike it is yet. I can say it is unlikely to be a good idea. Manafacturers select tire sizes on the basis of what will perform best. Putting on wider tires may cause the bike to handle worse than the recomended size.

    Welcome to the forum mattt. :)
  4. Assuming your first bike is going to be a 250 or LAMS bike I can't see any reason why you'd need to, or even want to. :? . Oh yeah welcome to the forums.
  5. Very true + of course they can rub against the suspension.

    My RGV 250 always handled like a complete turd which was strange as they had a reputation for being really good through the bends. When it was time to put some new rubber on it I discovered the previous owner had decided to fit wider tyres on it :?
  6. i have not bought a bike yet but yes, it will be a 250. I was assuming that wider tires would give me better traction/stability/grip, and to me it also looks alot more impressive!
    Thanks for the welcome guys :)

    edit: ah in that case again it is quite different to the way cars work thanks guys
  7. Nope, nope and nope. The recommended tire size will be most likely to provide optimum traction, stability and grip. You can always give it a go but I think you'll be wasting your money. :)

    And to everyone else it might look like the owner is a poser and puts wider tires on cause he thinks it looks faster that way. :wink:

    I don't think you're a poser. It was a relevant question, but to go ahead with the project might give other riders that impression. :D
  8. Nah mate don't worry about it, go with standard fitment until you understand the dynamics of a stocker before you go making adjustments that could cause all sorts of problems.

    Nothing wrong with the 2fiddys anyway, you can get ones like the 250 Hornet which come standard with a 180-section rear tyre as wide as a CBR1000RRR fireblade's!
  9. True there, the standard rear tyre on a 250 Kat is actually wider than the original 1100cc version :shock: (though the front is slightly narrower).
  10. I gotta say I do like a wider tyre, specially in the wet. They do contribute to a feeling of stability.

    Dropping into a corner hard on Cheng's Across (and I mean REALLY dropping, the thing dives and swoops in like crazy) is certainly a heart-in-mouth experience compared to the Hornbag which feels much more composed right over til you're nearly scraping pegs.
  11. Wider tyres mean slower turn-in.

    It will make you bike try to stand up mid corner and hard to hold a good line.............

    Bigger more powerul bikes need the extra grip, so are forced to use wider profiles, but the bikes are designed around that.
    You wont see the same size rubber on the smaller classes in the GP's, as it would throw their handling out the window.
    Smaller bikes are all about corner speed, while the larger ones are point and squirt......... you'll find the MotoGP bikes use a completely different profile to roadbike profiles also.
  13. ...slows down your steering.

    Have a look at the rears on a 125 GP bike...should tell you all you need to know
  14. Like Ratbag says -don't do it. When I bought my 400 it had only 1 size up tyre on the rear. Popped the standard size back on & it completely transformed the handling for the better.
  15. Apart from the changes in handling characteristics, (sometimes radically so), that come from fitting different size/profile tyres on a bike ...

    Also BEAR IN MIND what effect fitting non-standard tyres will/might have with regards to INSURANCE in the event of an "off".

    Anyways .. here's an Excel spreadsheet which enables you get a graphical comparison between tyre sizes/profiles you enter. It's about the best thing I've been able to find of it's type so far.

    Credit to Aaron Bohnen of UBC Civil Engineering/TCR Engineering for the spreadsheet ....

    Here's the link to the file in "native Excel format" ... http://people.aapt.net.au/~ralaw/Tyre_sect_v97_12.xls

    Here's the link for a "zipped" version of the same file ...http://people.aapt.net.au/~ralaw/Tyre_sect_v97_12.zip

    For a bike .. set the "offset" to zero as the tyre centres are "inline"

    Hope this is of some help ...
  16. dont do it unless you're building a drag-bike the doesnt need to corner!!