17x4.25 or 18x4.25 wheels for greatest choice of tubeless tyre?

Discussion in 'Parallel Universe' started by bastimentos, Feb 7, 2013.

  1. bastimentos

    bastimentos Been here awhile

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    Hey gents,

    So I am building a nice F800GS and have a good deal on either a 17x4.25 or 18x4.25 rear wheel to run tubeless tyres.

    I know very little about wheels and tyres, and was hoping that some people that do could help me understand which choice of these specific sizes (none other are available in my offer) would open up the greatest selection of tubeless tyres for the F800GS?

    Looking for the 50/50 tyres like a TKC80 etc

    Really appreciate the help, thanks!
    #1
  2. picard

    picard engage!

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    with that width rim your recommended tire size will be 150/70. I would think that 17" would offer you everything tubeless out there in that size. Also with that big a tire you might run into clearance issues when going to 18"
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  3. bastimentos

    bastimentos Been here awhile

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    Duly noted, one vote for the 17's registered. Thanks for the 150/70 heads up.
    #3
  4. bastimentos

    bastimentos Been here awhile

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    Found an interesting one here from Mitas - might be the ticket combined with a 21" TKC front.

    http://www.mitas.eu/index.php?stranka=300&scid=52&pid=2846

    Edit: Metzeler Karoo comes in a 140/80 - 18 M/C 70R TL - not sure if this would be another option if i was desperate to replace one and they had it in stock
    #4
  5. LukasM

    LukasM Long timer

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    What riding are you going to be doing? 17"x4.25" is a nice street size, 18"x4.25" is a bit weird because 18" tires are mostly off-road biased but the 4.25" is way too wide and will bend very easily.

    If you are getting a second wheel I would keep the stocker with a street tire and then add a 18"x2.5" or 3.5" for offroad.
    #5
  6. bastimentos

    bastimentos Been here awhile

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    Hi,

    Thank you for your thoughts, I would prefer to go to a 3.5 rear for strength offroad but I do not have that option (package deal with suspension and other bits) so its the specific options listed in 17x4.25 or 18x4.25 only.

    My riding will be 50/50 but I will not be riding at a speed offroad that would punish the rims, i've no deadlines when I head off pavement so I tend to travel in a more "sightseeing" pace and I hoped the wider (forged 7075 aluminum alloy) rim may hold up alright for that.

    That said, would the 18" option help increase clearance and roll over obstacles easier to a degree that it would be the one to go for? I know I will have to change the gearing to accomodate it but like I said before, I ride slow so I would prefer to have a bias towards making offroad easier than tearing up asphalt :)

    I appreciate your experienced opinion.
    #6
  7. bastimentos

    bastimentos Been here awhile

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    Screw it, I can't find anything worthy aside from the E09 Dakar - but that looks like it will do the trick so 18" it is :clap
    #7
  8. FredRydr

    FredRydr Danger: Keep Back 500 Ft.

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    [​IMG]
    I was slabbing home on my '09 F800GS from Ohio to central Pennsylvania last night, and I thought that if I had a flat at 11:00PM alongside the Pennsylvania Turnpike in 40F degrees, I'd be wishing they were tubeless. I have two sets of wheels, and had swapped out the TKC80s for the Scorpions because I knew this trip would be paved roads only. It brings me back to considering sending one set to Woody's Wheelworks to install a new front rim and sealing both so I can run one pair of street tires without tubes.

    But then again, I don't use the street tires very often. Decisions, decisions.... :bmwrider

    Fred
    #8
  9. rmhrc628

    rmhrc628 Long timer

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    Who even makes an 18inch bigger than 2.5?

    If the 18inch wheel and tire combo is taller than the 17inch combo then yes your bike will glide over rough terrain far easier. The bike should also handle a little better as I think the 18in tires are lighter.

    All bets are off if I'm wrong on my contention :)
    #9
  10. bearclaw952

    bearclaw952 n00b

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    Woody won't seal the front because there's no safety bead on the rim. You can do it yourself though.
    #10
  11. FredRydr

    FredRydr Danger: Keep Back 500 Ft.

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    That's why the rim would be replaced.

    Fred
    #11