Star Nut iInstallation Help Needed!

zebedeecp
zebedeecp Posts: 63
edited September 2007 in Workshop
Having purchased new set of forks I now need to know how to install the star nut forthe threaded bolt. does anyone know how this can be done easily so that the nut is square in the steering tube.

Comments

  • whyamihere
    whyamihere Posts: 7,715
    Easiest way: Take it to a bike shop. There's a special tool to set the crown race in square. If you want to do it yourself, you can buy the tool here.

    The alternative method is to put the bolt through the star nut and hit the bolt to push the star nut in. Can be quite difficult to get it in straight though.
  • Bronzie
    Bronzie Posts: 4,927
    Here's how I do it:
    - put the bolt into the star nut
    - find a tubular hexagon wrench (or spark plug spanner) that just fits over the star washer bolt (about 8 or 10mm spanner from memory) - or you could use a short length of steel tube of smallish diameter - like a bathroom towel rail
    - clamp the steerer tube of the forks in a workbench so that the fork legs are just resting on a block of wood (for protection of the fork lugs) on the garage floor - if its a carbon steerer, use something to protect the steerer from crushing
    - gently tap the top of the hex wrench with a hammer to knock the star washer down into the steerer - take care to get it in straight and don't knock it down so far that the bolt is then too short to reach the washer with the aheadset top cap and spacers in place!

    Using the tube to knock the washer down makes it easier to put in straight and prevents damage to the threads in the washer.

    To be fair, it is a bit of a faff - if you have just splurged on an expensive set of new forks, the LBS is probably the safest option!
    It's a Lifestyle! -+-+- Coggan Training Levels
  • Smokin Joe
    Smokin Joe Posts: 2,706
    I use a mole grip to bend the tabs of the star nut in a little then give it a few firm clouts with a wood or rubber mallet. I have never had a problem with getting them in square as they self-align once the top part of the nut goes into the tube.
  • whyamihere
    whyamihere Posts: 7,715
    Bronzie wrote:
    if its a carbon steerer, use something to protect the steerer from crushing
    You shouldn't put a star nut into a carbon fork anyway.
  • aracer
    aracer Posts: 1,649
    A recommendation I've seen elsewhere, but not yet tried is to pull the starnut in instead of bashing it in. To do this you get a length of M6 studding which will thread into the starnut, run this through the steerer and into the bottom of the starnut, then using washers and a nut at the bottom of the steerer pull it down into place in much the same way as pressing headset cups. Should be much easier to control the way it goes in than bashing with a hammer, and the forces should also help it to go in straight.
  • Bronzie
    Bronzie Posts: 4,927
    whyamihere wrote:
    You shouldn't put a star nut into a carbon fork anyway.

    ...............is the right answer - just making sure you're are still awake at the back there!

    Carbon steerers need an expanding plug fixing that has rubber o-rings that grip the inside of the steerer without damaging the carbon.
    It's a Lifestyle! -+-+- Coggan Training Levels
  • nicklouse
    nicklouse Posts: 50,675
    Bronzie wrote:
    whyamihere wrote:
    You shouldn't put a star nut into a carbon fork anyway.

    ...............is the right answer - just making sure you're are still awake at the back there!

    Carbon steerers need an expanding plug fixing that has rubber o-rings that grip the inside of the steerer without damaging the carbon.

    and also check the fork makers recomendations for the length of steerer permited between headset and stem and also if the steerer should be cut level with the top of the stem (as opposed to the normal below the top of the stem for an aluminium steerer).
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • aracer
    aracer Posts: 1,649
    nicklouse wrote:
    also if the steerer should be cut level with the top of the stem (as opposed to the normal below the top of the stem for an aluminium steerer).
    How does that work then? Are there forks which insist you have a spacer above your stem (as otherwise it's impossible to get the top cap to tighten down on the stem properly if you don't cut the steerer below the top of the stem)?
  • nicklouse
    nicklouse Posts: 50,675
    correct. it has to do with the clamping forces from the bolts on the stem.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • aracer
    aracer Posts: 1,649
    Given none of the piccies I found in a quick search (Eurobike and pros racing) had a spacer on top of the stem, they can't be that common - give me an example.
  • nicklouse
    nicklouse Posts: 50,675
    more in the mtb world. but as i said always follow the fitting info.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown

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