20" Wheels with 14mm Axles and Disc Brakes?

jimcroisdale
jimcroisdale Posts: 11
edited October 2016 in MTB workshop & tech
Hi all,

First post here - hoping you can help me!

I'm building a gravity racer and am looking at the kind of wheels I need. Essentially, the spec is looking like:

- 20"
- 14mm axles (not 3/8 as they are not strong enough to handle the lateral loads)
- Disc brakes

Is this a beast that I can get off the shelf, or am I going to need to be lacing BMX rims onto MTB hubs and other tomfoolery?

Regards,

Jim

Comments

  • The Rookie
    The Rookie Posts: 27,812
    You'll be building your own....do you mean 15mm axles?
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • rockmonkeysc
    rockmonkeysc Posts: 14,774
    Bigger axles are good for reducing twisting in forks which I wouldn't have thought would be an issue in your application.
    The main thing you want is super stiff rims. Discs might be easier to mount on the axle. You're going to find it difficult to run four brakes off two levers, you'll never get the fluid displacement you need.
  • The Rookie wrote:
    You'll be building your own....do you mean 15mm axles?

    From what I've seen, axles are either 3/8" or 14mm, and I'll need the 14mm ones as I'm using stub axles, so the wheel is only supported from one side.

    That's also why I can't mount the discs on the axle - the axle won't be rotating.

    Cheers,

    James
  • The Rookie
    The Rookie Posts: 27,812
    Not heard of a 14mm standard for bikes, fronts would be 9,12,15 or 20mm.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • larkim
    larkim Posts: 2,474
    Seems its a BMX thing

    https://www.google.co.uk/search?q=bmx+s ... m+bmx+axle

    So if BMX 14mm axle is a requirement, then BMX hubs would be required.
    2015 Canyon Nerve AL 6.0 (son #1's)
    2011 Specialized Hardrock Sport Disc (son #4s)
    2013 Decathlon Triban 3 (red) (mine)
    2019 Hoy Bonaly 26" Disc (son #2s)
    2018 Voodoo Bizango (mine)
    2018 Voodoo Maji (wife's)
  • 15mm would be fine also - it's just a question of strength. At 3/8in i couldnt get an axle strong enough to support the wheel at only one side.

    20" wheel, 14mm (or thicker) axle, disc brake mount.

    Anything out there?

    Cheers,

    Jim