Headset questions.

[compo]

The headset on my Trek 7.3 FX is described as an "Aheadset Slimstack With Semi-Cartridge Sealed Bearings".

The headset on modern bikes (post quill stems) is something I have never touched. I know enough to take up any play in the headset, but do I need to do any further maintenance and just what are semi-cartridge sealed bearings?

Obviously the best way to find out is how I have always learned to do something, dive in and see what happens, but I must admit to being happier if I know roughly what will happen when I undo something!

 

[lpretro1]

With 'ahead' type the stem clamps onto the fork steerer by two bolts - rather than being pushed down inside it and then tightened with an expander bolt. Once inside the 'gubbins' of the headset will look the same. Slimstack refers to the profile of the headset cup - instead of overhanging the steerer tube they fit close in and have very little stack height - gives a nice smooth profile. Inside the cartridge type bearing means you won't see lots of ball bearings - otherwise as you'd expect. To replace bearings you need to undo the clamp bolts on the stem lift it (plus any spacers) off and this gives you access to the headset itself. Bearings should just lift out - you need to make sure the replacement bearing has same angles to it - it should say on the bearing itself. Once replaced then refit spacers and stem and do clamp bolts up to correct torque - job done.

 

[compo]

Thanks for that. I have been looking on You Tube and had a pretty god idea but one question remains, do you need to grease the bearing cartridge when assembling the headset, if for no other reason than to give it some moisture protection.

 

[Cubist]

Cartridge bearings rarely come with enough grease in them. Hope are notorious for being dry or at least dryish. If you are careful you can pick out the seal with a pick ( I use a sewing pick) and add some grease, before carefully refitting the seal. This will also help to rejuvenate an elderly seal during a service if you like being thorough. Mind you don't damage the seal though, one little nick and you might as well bin it if its anywhere where it can get wet.

A layer of grease on the outside won't hurt and as you say, could stop a bit of water ingress.

 

[Blue Hills]

Yes, I've been led to believe that a bit of grease won't do any harm to help keep moisture at bay.

Ipreto1: >>Inside the cartridge type bearing means you won't see lots of ball bearings

Well doesn't apply to the Dahon Speed Pro which has a habit of reducing a cartridge bearing to its constituent parts

Folk who know more than me might disagree but I rather like the simplicity of ball bearings - I think FSA do a aheadset that uses ball bearings, "The Pig" maybe? I know servicing is more complicated but if the thing is very tough to start with you won't have to do much with it anyway - took my pushing 15 year old steel Ridgeback to a Dr Bike a few weeks ago and the guy said that old steel headsets tend to last forever - I've definitely never touched it.

Caution as above - my views/perspective may have been influenced/warped by dealing with Dahon.

Chain Reaction is a good source of cartridge bearings for common aheadsets - eventually I think I've managed to deduce what is in the Dahon - Dahon would never tell me!

 

[Blue Hills]

PS: Do let us know how you get on compo - I'd be interested.

 

[compo]

PS: Do let us know how you get on compo - I'd be interested.

I haven't had the bike long enough to worry about the headset, I was really enquiring for the future. Taking the advice above, and viewing You Tube, the job looks easy when I eventually do have to do it.

Like you I had an old Ridgeback with old style headset. Last time I serviced it the bearing surfaces were as good as new.

 

[Blue Hills]

I'm planning to take a look inside the Ridgeback ball bearing wonder soon anyway Compo - I can feel a very very slight drag on it but hell it's only got to turn, not propel the bike.

In my thirst for knowledge about cartridge headsets I did find a techdoc from Cane Creek (who I have the impression are a decent company as companies go) and was alarmed to find something to the effect that their headset had been designed for lightness, not longevity. And it then effectively said the bearings were a consumable with a pretty short life - 1 or 2 years rings a bell.
Madness I tell you, madness, unless you're a budding Wiggo or Cav.