9mm Axle forks to 15mm

Nijinsky
Nijinsky Posts: 35
edited October 2013 in MTB buying advice
I have a rockhopper 2011 and i've hovering over the buy button for some forks. I hear 15mm is better than the standard? Should I plump for them and will they fit my bike without any other modifications?

Comments

  • nicklouse
    nicklouse Posts: 50,673
    no idea. what forks? are your wheels switchable? I guess not so new wheels as well.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • sorry i am looking at reba rl's

    http://www.rczbikeshop.com/anglais/rock ... white.html

    had a feeling i might need to switch wheels.
  • jairaj
    jairaj Posts: 3,009
    Unless your hubs are convertible to a 15mm axle you will need new hubs too.

    15mm axles can help stiffen the fork up but the rest of the fork chassis can make big difference too.

    If you notice a lot of wheel twist and you have budget for the wheels then yeah might be worth it.

    But before you do what are your current forks and what are you looking to upgrade to?
  • jairaj wrote:
    Unless your hubs are convertible to a 15mm axle you will need new hubs too.

    15mm axles can help stiffen the fork up but the rest of the fork chassis can make big difference too.

    If you notice a lot of wheel twist and you have budget for the wheels then yeah might be worth it.

    But before you do what are your current forks and what are you looking to upgrade to?

    Current forks are the standard Suntour XCR, which are now knackered. So im taking the oppourtnity to upgrade. I like the look of the reba's but unsure of the 2013 ones as they have changed to solo air? any negatives? Worth going for the 2012 dual air ones instead?
  • jairaj
    jairaj Posts: 3,009
    Solo air is simpler and more reliable. Dual air is more adjustable but if you don't know what you're doing you can loose performance.

    Most people tended to run their dual air forks with the same pressure in both cambers giving you the same result as solo air.

    The Reba is a nice fork and that's a good price should be a good upgrade if you can afford to change the front wheel too.
  • rockmonkeysc
    rockmonkeysc Posts: 14,774
    I have the dual air Rebas. Personally I would prefer solo air. The dual air spring can be unreliable.
    Rebas aren't a particularly stiff fork, I notice quite a lot of flex in mine even with the 15mm axle and tapered steerer.
  • Thanks guys.

    Bought these http://www.rczbikeshop.com/anglais/rock ... e-red.html

    kept to 9mm and went for the Dual purely because they were a bit cheaper than the new 2013 range. Not sure why they are so cheap compared to everywhere else! cheapest i could find these anywhere else was £300
  • http://www.sram.com/service/rockshox/103,439 Check this out , particularly the tuning guide .I have dual air sids.pay attention to setting sag correctly and don't just rely on rockshox recommended air pressures for rider weight. In my opinion and experience they are set far too high.

    It's easy to get confused with air forks . I would advise only making small adjustments to one thing at a time I.e pressure, damping , rebound. Whilst riding a familiar route. You can take a shock pump out with you but note a difference of just 5 psi can be quite dramatic.
  • Twelly
    Twelly Posts: 1,437
    I found a simple way of setting up the dual air that worked for me..
    Add air to the + chamber to get 25-30% sag (or however much you want)
    Add air very slowly to the - chamber until you notice the fork just starting to pull down in its travel. You have to look very closely and add air one pump at a time.

    My Reba always felt great after setting up like this.
  • jairaj
    jairaj Posts: 3,009
    Sag should be set with equal pressures in the positive and negative chambers