How do I..

[Milo]

Smash out and install a new star fangled nut without going horribly wrong?

 

[rustychisel]

Firstly, why?

Secondly, they can be hard to get out - usually your best chance is driving it right through and out the bottom of the fork - if that can be done.

A replacement should be tapped carefuly into position - don't drive it too deep - and use a drift (a piece of metal tubing) to ensure it is straight.

 

[bonj2]

you really need a special tool to install the new one. It's probably possible to do it without but the chances of it going wrong are higher.
What you want is a park tools 'threaded nut setter' tool, about £15. or alternatively get a bike shop to do it.
To remove the old one, either bang it out the bottom with a mallet and a long rod, OR just see what happens when you tighten the top cap far too tight.

but again, why do you need to?...

 

[Twenty Inch]

If you have a suitable drill bit, you could drill out the centre and let the bits drop out the bottom. Less of the smashing, please.

 

[RedBike]

To get the old one out either tap it all the way through or start hacking at it with a drill, hacksaw blade.

To put the new one in, put a spare bolt in the star nut and tap it into place (taking extreme care to make sure it stays straight.)

 

[Smokin Joe]

Just tap the old one down an inch or two and leave it there, it is not worth sodding about trying to remove it unless you are a real weight saddo.

To install a new one, just get a large pliers and bend the tabs inwards until it taps in easily.

 

[Milo]

I sort of snapped mine by accident (dont ask)

 

[simonali]

I sort of snapped mine by accident

How did you manage that?

 

[bonj2]

I'm guessing, either:
a) tightened the top cap too tight,
or, more likely -
tried to install it without the correct tool and gave it a good whack when it was in wonky

am i right miloat, i am aren't I

 

[Milo]

No you are wrong with b bonj it was indeed A.
It seems to still be tight enough though might not bother.

 

[02GF74]

No you are wrong with b bonj it was indeed A.
It seems to still be tight enough though might not bother.

the cap bolted to the SF nut is only keeping the headset bearings at the correct setting so if it goes loos or falls off, you will get some knocking rom the headset.

the two nuts on the side of stem keep the bars on the bike point in the right direction and stop the forks from dropping off!! these should be tight.

 

[Milo]

They are

 

[TheDoctor]

the cap bolted to the SF nut is only keeping the headset bearings at the correct setting so if it goes loos or falls off, you will get some knocking rom the headset.

the two nuts on the side of stem keep the bars on the bike point in the right direction and stop the forks from dropping off!! these should be tight.

Not quite. You loosen the stem bolts first, then set the headset bearings, then tighten the stem bolts again. This locks everything down, keeping the headset bearings set as they were.
The cap sets the bearings, but the stem keeps them set after that.
And Sheldon can explain it better than me, I suspect.

 

[k-dog]

the cap bolted to the SF nut is only keeping the headset bearings at the correct setting so if it goes loos or falls off,

No, it's not.

It's there to give you the correct setting before you tighten the stem bolts - after the stem bolts are tight you could then remove the cap. There's no point though.

Once the stem is tightened in position that's what is keeping the bearings under compression.