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Avon tyres... bummer...

Discussion in 'Norton Commando Motorcycles (Classic)' started by Fast Eddie, Jan 13, 2020.

  1. Fast Eddie

    Fast Eddie VIP MEMBER

    Joined:
    Oct 4, 2013
    Am I missing something in this link:

    https://www.avontyres.com/en-gb/tyres/roadrider?cartype=motorcycle

    Looks like Avon have dropped the imperial sizes for RRs. Meaning that my favoured combo of 19” front (universal) and dedicated 18” rear, that have the same rolling radius, are now defunct.

    As is the 19” universal.

    And the dedicated rear 18” that would fit in a Commando.

    The 110 / 18 that they do is a universal, which has less tread depth than a dedicated rear and this a much reduced life.

    Looks like they’ve tried really hard, and succeeded, in making RoadRiders a shit choice for Commando owners (and a whole list of other classic bikes) !

    Can someone please remind me what the options are elsewhere, the Continentals are popular with some of y’all if I recall correctly...
     
  2. MichaelB

    MichaelB VIP MEMBER

    Joined:
    Jan 14, 2004
    Fast Eddie likes this.
  3. maylar

    maylar VIP MEMBER

    Joined:
    May 13, 2007
    Wasn't there a thread here a bit ago about the new version of those coming out soon?
    I'm still seeing AM26 universals being listed.
     
  4. kommando

    kommando

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    May 7, 2005
    NPeteN likes this.
  5. Fast Eddie

    Fast Eddie VIP MEMBER

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    Oct 4, 2013
  6. maylar

    maylar VIP MEMBER

    Joined:
    May 13, 2007
    Yeah... those.
     
  7. Staytite

    Staytite

    Joined:
    Oct 15, 2011
    Coincidentally I am about to order two tyres to replace my old road runners

    I have measured the actual worn tyres on my Commando:
    • Front 90/90/19 actual width 95mm & diameter 646 mm fitted to Akront 1.85"
    • Rear 110/90/18 actual width 116mm & diameter 658 fitted to unknown rim
    Obviously the rim affects the width & height of the tyre, but it would seem I previously chose tyres with different diameters
    with the rear being "taller" than the front, which is presumably not good?

    Although on radius the difference is half 323mm (front) vs 329mm (rear) and as the rear wears it will become closer to that of the front.

    On the newly revised Avon web site perhaps the better (?) choice is
    • Front 90/90/19 spec width of 99mm & diameter of 647mm
    • Rear 110/90/18 spec width of 111mm & diameter of 640mm
    This gives the rear radius (320mm) as "lower" than front (323mm) which is opposite to my current tyres and as it wears the rear will become lower.

    Or perhaps I should have a pint of fine ale and stop worrying about a few mm

    Perhaps after Brexit we can have proper Imperial tyres and proper pints instead of 500ml:)
     
  8. Torontonian

    Torontonian

    Joined:
    Dec 28, 2009
    The BT 45's are quite good on the Commando , affordable and available.
     
  9. Staytite

    Staytite

    Joined:
    Oct 15, 2011
    ah .... MK11 ....should have had a pinto_O
     
  10. Fast Eddie

    Fast Eddie VIP MEMBER

    Joined:
    Oct 4, 2013
    Thanks for that, very informative.

    For those of a 19” front and 18” rear configuration (like me), the following looks like a good set up, which should be fine so long as you keep below 130mph...


    Front: 100/90-19 M/C 57H W (it has a diameter of 663mm)
    Rear: 110/90-18 M/C 61H TL (it has a diameter of 658mm)
     
    Last edited: Jan 13, 2020
  11. MichaelB

    MichaelB VIP MEMBER

    Joined:
    Jan 14, 2004
    Your Welcome.
    That's the combo I am running on the H1. I like them ALOT......
    In hindsight, I question whether I should run the 400/18 on the stock rim, decreasing the trail a tad.
    (Edit, I remember now, not available at the time)

    The 110/90-18 is 658 BTW. Typo I'm sure....
     
    Last edited: Jan 13, 2020
  12. grandpaul

    grandpaul VIP MEMBER

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    Jan 15, 2008
    I think that fits 95% of the Commandos on this site...
     
  13. MichaelB

    MichaelB VIP MEMBER

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    Jan 14, 2004
    Yup, but he's on the short list of those who could exceed it.....
     
  14. illf8ed

    illf8ed VIP MEMBER

    Joined:
    Dec 30, 2003
    I see Roadrider II 100/90-19 on Avon’s website. That’s what I use front and back on my ‘72.
     
  15. Fast Eddie

    Fast Eddie VIP MEMBER

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    Oct 4, 2013
    And now that they no longer do a suitably sized dedicated 18” rear, your set up would appear to be as good as any.
     
  16. Fast Eddie

    Fast Eddie VIP MEMBER

    Joined:
    Oct 4, 2013
    Correct, now amended to avoid confusion.
     
  17. illf8ed

    illf8ed VIP MEMBER

    Joined:
    Dec 30, 2003
    I have a new set of 100/90-19 AM9 that came with my new ‘69 750 S project. Will use these when the Roadriders are worn out. The ‘69 is going to get Avon Safety Mileage/Speedmaster tires of the correct size, 100/90-19 fouls the front fender. The rear Safety Mileage has a tread pattern very similar to Avon GP that was original equipment.
     
    Fast Eddie likes this.
  18. dero

    dero VIP MEMBER

    Joined:
    Jan 22, 2010
    another vote for the bridgestone BT45's .
    Have had these the last 3 times , very happy with them .
     
  19. Staytite

    Staytite

    Joined:
    Oct 15, 2011
    Hi Eddie,

    I'd be interested to know why you do not seem to like the Avon Roadriders:

    Front Mk1 90/90/19 99mm 647mm
    Front Mk2 90/90/19 99mm 647mm

    Rear Mk1 110/80/18 111mm 640mm
    Rear Mk2 110/80/18 111mm 640mm
    Rear Mk2 100/90/18 108mm 642mm

    They all seem to be smaller in diameter than the original tyres and the other tyres you are contemplating,
    is this the reason?

    Thanks
    Staytite
     
  20. Fast Eddie

    Fast Eddie VIP MEMBER

    Joined:
    Oct 4, 2013
    Only one reason. All of those rear tyres you show are not rear tyres, they’re universal fitment.

    They therefore only have 5.6mm tread depth. A dedicated rear tyre has 34% more depth at 7.5mm.

    Thats 34% more mileage... and less cost... and less tyre changing aggro.

    Being nice and sticky, Roadriders don’t last too long anyway. I just find it frustrating to have to change them EVEN more often just cos it suits Avon!

    With a shed full of bikes, reducing the cost and aggro is nice...
     

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