Servicing a Headset

[Slick]

Looks to me like the inner race of the bearing is still stuck in there.

There is clearly a piece of the old race there. Need to get it off first.

I think it's the bottom part of the bearing and the compression ring but I'm unsure.

I've left in dripping in plusgas and pulled out the old cannonball for the morning. Ever wished you just took it to someone who knew what they were doing?

 

[rogerzilla]

You could tap off the crown race. It will probably come apart easier once the crown race isn't being stretched by its seat.

 

[Slick]

You could tap off the crown race. It will probably come apart easier once the crown race isn't being stretched by its seat.

Nothing is moving off that with a tap. I'm frightened to batter it with the force it actually requires to move in case I'm hitting the wrong thing.

I'll give it another soaking in plusgas in the morning and see what I can do after work.

 

[rogerzilla]

Both bearings take exactly the same amount of weight as they share the load

It's nice to think so but it doesn't work like that in practice, unless the headset has a substantial preload. The weight of the rider and any road shocks load the lower race and unload the upper race. If the headset is nipped up just so play is removed (which is normal) the slightest elasticity in the system will mean the top race takes virtually no shock loads.

Brinelling is indeed the main cause of failure in traditional headsets but is largely cured by headsets which incorporate a large angled plain bearing surface to take the rocking loads (all cartridge headsets and roller bearing headsets with loose raceways, like the Stronglight A9). I used to have the old 1055 headsets go notchy on me in less than 1000 miles but a modern Cane Creek can run for ten years without attention. I've just moved an S2 between frames after that long in service.

 

[midlife]

I think Yellow Saddle mentioned fretting rather than brinelling

 

[Yellow Saddle]

It's nice to think so but it doesn't work like that in practice, unless the headset has a substantial preload. The weight of the rider and any road shocks load the lower race and unload the upper race. If the headset is nipped up just so play is removed (which is normal) the slightest elasticity in the system will mean the top race takes virtually no shock loads.

Brinelling is indeed the main cause of failure in traditional headsets but is largely cured by headsets which incorporate a large angled plain bearing surface to take the rocking loads (all cartridge headsets and roller bearing headsets with loose raceways, like the Stronglight A9). I used to have the old 1055 headsets go notchy on me in less than 1000 miles but a modern Cane Creek can run for ten years without attention. I've just moved an S2 between frames after that long in service.

There is substantial preload on any well-adjusted headset otherwise it will knock.

Just "nipping it up" is not normal in engineering, whatever nipping it up means.

We preload bearings.

Besides, there is no brinelling in a headset bearing. Any damage is from fretting, not impact.

 

[Yellow Saddle]

I think it's the bottom part of the bearing and the compression ring but I'm unsure.

I've left in dripping in plusgas and pulled out the old cannonball for the morning. Ever wished you just took it to someone who knew what they were doing?

Plusgas, pork drippings, WD 295 - none of that stuff works when something is press-fit or rusted.
Judicious force is called for.

 

[Yellow Saddle]

Surely you've got the weight of the frame and more of the riders weight on the top bearing?

Draw a force diagram and you'll see that your scenario is implausible.

 

[Slick]

Plusgas, pork drippings, WD 295 - none of that stuff works when something is press-fit or rusted.
Judicious force is called for.

In that case, I need to disconnect the brakes and get it in a vice.

I was always good at smashing things, just wasn't always the right thing that got it.

 

[Yellow Saddle]

In that case, I need to disconnect the brakes and get it in a vice.

I was always good at smashing things, just wasn't always the right thing that got it.

A vice won't help, but getting the fork off the bike will give you some better options.

You'll notice that it is impossible to get a chisel/screwdriver to grab hold of the offending part in order to hammer it off. But if you want to try....invert the fork so that the top of the steerer rests on something semi-solid like a piece of hardwoord, have a helper hold the fork for you in the inverted position while you bang away with a screwdriver/chisel at the race.

Blood will flow, curses will be cursed.

Find a ball-joint separator somewhere with a knife-edge to separate it. Bike shops have the right tool, if they are worth their salt.

 

[Slick]

A vice won't help, but getting the fork off the bike will give you some better options.

You'll notice that it is impossible to get a chisel/screwdriver to grab hold of the offending part in order to hammer it off. But if you want to try....invert the fork so that the top of the steerer rests on something semi-solid like a piece of hardwoord, have a helper hold the fork for you in the inverted position while you bang away with a screwdriver/chisel at the race.

Blood will flow, curses will be cursed.

Find a ball-joint separator somewhere with a knife-edge to separate it. Bike shops have the right tool, if they are worth their salt.

I know the very man to ask.

Thanks for your input.

 

[Slick]

A vice won't help, but getting the fork off the bike will give you some better options.

You'll notice that it is impossible to get a chisel/screwdriver to grab hold of the offending part in order to hammer it off. But if you want to try....invert the fork so that the top of the steerer rests on something semi-solid like a piece of hardwoord, have a helper hold the fork for you in the inverted position while you bang away with a screwdriver/chisel at the race.

Blood will flow, curses will be cursed.

Find a ball-joint separator somewhere with a knife-edge to separate it. Bike shops have the right tool, if they are worth their salt.

One last question, I know it's probably easy enough if you know what you are doing but do I need to do anything specific before disconnecting the brake cable to ensure it goes through the internal routing on the fork?