Author Topic: Odd wear pattern on front tire.  (Read 2366 times)

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  • Offline broderp   us

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    Offline broderp

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    Re: Odd wear pattern on front tire.
    Reply #10 on: Oct 25, 2021, 03.49 am
    Oct 25, 2021, 03.49 am
    *Originally Posted by zed9 [+]
    Broderp, what pressures are you running?
    Stock pressures as called out in the manual.  36 and 42 psi.

  • Offline broderp   us

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    Re: Odd wear pattern on front tire.
    Reply #11 on: Oct 25, 2021, 03.58 am
    Oct 25, 2021, 03.58 am
    *Originally Posted by 3alfa3 [+]
    You dont brake hard, so no wear in the centre: front tire is not under stress when maintaning speed (or accelerating). But when you go into a lean, tire is under stress, it is not only rotating freely, but there is a force that pushes the tire and tire fight that with friction. That is the wear you have.
    As seen from you pictures, you dont lean much, and on straight you probably not breaking much (or hard) so your front tire is not stressed and used much, but in (half)lean, it is wearing more because of friction. Your rear tire is showing typical wear for that kind of riding: center is more under stress (accelerating but also maintaning speed because it is driven by engine unlike front tire) and you dont accelerate (hard enough) when in lean to wear the rear tire uniformly.
    In that scenario, higher pressure is your friend, it will wear in the same pattern as now, but not so fast. Btw, dont go over 42 psi cold for the rear, for the front, try 38, maybe even 40 psi (considering your weight)

    Sorry for bad english

    Thank you for taking the time to analyze my pics and provide feedback. You are spot on about my riding habits. What you say makes sense as well.  I also believe that for some reason my front suspension has gotten stiffer, as evidence by my wire tie - even on the bad road I am not using enough of the available travel.  Perhaps if I soften it a bit, the front tire will take less of a beating during turns and last longer. ?  (I've not messed with it at all as initially I was getting about 80% suspension travel and not bottoming out.

  • Offline zed9   us

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    Re: Odd wear pattern on front tire.
    Reply #12 on: Oct 25, 2021, 04.21 am
    Oct 25, 2021, 04.21 am
    The zip tie won't go all the way down to the axle casting. I forget what the measurement is but it's not at the bottom.

  • Offline 3alfa3   hr

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    Offline 3alfa3

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    Re: Odd wear pattern on front tire.
    Reply #13 on: Oct 25, 2021, 07.22 am
    Oct 25, 2021, 07.22 am
    *Originally Posted by broderp [+]
    Thank you for taking the time to analyze my pics and provide feedback. You are spot on about my riding habits. What you say makes sense as well.  I also believe that for some reason my front suspension has gotten stiffer, as evidence by my wire tie - even on the bad road I am not using enough of the available travel.  Perhaps if I soften it a bit, the front tire will take less of a beating during turns and last longer. ?  (I've not messed with it at all as initially I was getting about 80% suspension travel and not bottoming out.

    That's geometry problem, not stiffness in front suspension (given your weight) - rear is collapsed under weight.
    .
    First you need to add preload to the rear shock (go full 5-6 turns in and measure rider sag then add more preload if needed). That is going to bring rear side up and put more weight to the front.
    You need static sag (10mm would be OK), but with your weight, more important is rider sag but dont go below 5mm of static sag and whatever rider sag you have then (maybe that will be 8-9 visible threads on shock, stock is 2 visible threads).

    I weight 203lbs without gear and have 7 visible threads on rear shock (stock is 2), stock 1.5 turn out for rebound. Front forks stock preload (11 turns in) and 2-3 clicks out for rebound.
    Rider sag is 37mm front, 44mm rear (rear static sag is 10-11mm). My bike is 2020 Z900 (EU model), that bike have stiffer spring in rear shock than 2017-2019 models, but not much stiffer.
    I use typically 100-110mm of fork travel, rarely more than that (120mm is max travel).
    Last Edit: Oct 25, 2021, 07.35 am by 3alfa3

  • Offline 3alfa3   hr

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    Offline 3alfa3

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    Re: Odd wear pattern on front tire.
    Reply #14 on: Oct 25, 2021, 07.24 am
    Oct 25, 2021, 07.24 am
    *Originally Posted by zed9 [+]
    The zip tie won't go all the way down to the axle casting. I forget what the measurement is but it's not at the bottom.

    I also forget actual number (did measured last year), but it is in the range of 11-15mm before casting (measured from tip of the seal to the casting, not outer tube to the casting).
    Last Edit: Oct 25, 2021, 07.30 am by 3alfa3

  • Offline broderp   us

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    Re: Odd wear pattern on front tire.
    Reply #15 on: Oct 25, 2021, 06.00 pm
    Oct 25, 2021, 06.00 pm
    *Originally Posted by 3alfa3 [+]
    That's geometry problem, not stiffness in front suspension (given your weight) - rear is collapsed under weight.
    .
    First you need to add preload to the rear shock (go full 5-6 turns in and measure rider sag then add more preload if needed). That is going to bring rear side up and put more weight to the front.
    You need static sag (10mm would be OK), but with your weight, more important is rider sag but dont go below 5mm of static sag and whatever rider sag you have then (maybe that will be 8-9 visible threads on shock, stock is 2 visible threads).

    I weight 203lbs without gear and have 7 visible threads on rear shock (stock is 2), stock 1.5 turn out for rebound. Front forks stock preload (11 turns in) and 2-3 clicks out for rebound.
    Rider sag is 37mm front, 44mm rear (rear static sag is 10-11mm). My bike is 2020 Z900 (EU model), that bike have stiffer spring in rear shock than 2017-2019 models, but not much stiffer.
    I use typically 100-110mm of fork travel, rarely more than that (120mm is max travel).

    Thanks, I will look into this.  If the wear on my tires can be caused by the suspension setup, then I need to look deeper into this.   Suspension stuff is somewhat confusing to me.   I can follow what you are saying, but don't know if I can effectively analyze and understand the results.   

    It doesn't help that I have no one to assist with measuring.  I am not aware of any reasonably priced places to take it to to have this done.   The few places will want to sell me a new suspension system, rather than help make what I have work just a bit better until such time that I can spring for a $$$$$$ on a new suspension setup.

  • Offline Cazzy_R   england

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    Re: Odd wear pattern on front tire.
    Reply #16 on: Oct 25, 2021, 07.37 pm
    Oct 25, 2021, 07.37 pm
    *Originally Posted by broderp [+]
    It doesn't help that I have no one to assist with measuring. 

    What you really need for one man suspension measurement and adjustment is a front wheel chock. A very handy tool.  :038:
    Tighten it 'til it strips then back it off half a turn.