Headset Notchy

Location
Edinburgh
Look for the section headed "Indexed Steering" ("Brinelling")
 

Globalti

Legendary Member
You need to replace the headset bearings some time soon. If you tighten them to take out the slack in the straight forward position they will be too tight when turning and the bike will have an odd feel to it, sort of rolling from side to side as the steering will be unable to comply with your tiny balancing steers and you'll be forced to over-compensate.
 

nigelb

New Member
If you are going to replace the headset, I would take the bike to a shop so you get the right bits.

Sometimes, you end up having to buy 2 headsets, to get races which will fit the frame (different diameters top and bottom on by Claud Butler).

Tools for the job for me were a big long screw-driver, a hammer, a lump of 1" x 2" wood, and allen keys (or spanners/grips, depending on the type). You also need grease - advice I was given was to pack the grease in so it squeezes out when you re-assemble, that way you know it isn't "dry".

Ideally, you need to detach all the cables from the handlebars, front wheel off, mudguard off, then that gives you a chance to work.

I'd allow at least a couple of hours if (heaven forbid) I have to do a third anytime soon!

Nige
 

zacklaws

Veteran
Location
Beverley
I had this last year on a club ride and it was most unpleasant, the steering was totally screwed up and it was more like tacking in a sailing boat than steering on a bike. You was for ever having to readjust your line. I cured it by just readjusting the headset as I feel I may have had it too tight when I had done some work on the headset. Anyway about 10 months later its still perfect with no loose play or brinneling.

Recently though it has started on my new road bike, but it only happens after it has been stood still for a while, the steering seems to lock in the forward position, but if I turn the steering left and right, it eases up and is then Ok, so I am not sure if it is brinneling or maybe just sticking. Once again readjusting the headset improved it.
 

ASC1951

Guru
Location
Yorkshire
reiver said:
As I won't get round to fixing it for a while, how safe is the bike to ride? could there be some sort of catastrophic failue?
Still safe to ride, but at the moment you might just get away with new bearings, which is a quick and cheap task. If you put a lot more miles on it, you will probably have to change the headset races as well, which is much more expensive because for most of us it is an LBS job.
 

Globalti

Legendary Member
Remove the forks and have a good look at all four races. If you can see an even grey track all round with no pitting, rust or cracking, you'll be fine with new balls and plenty of grease.

Some people make the mistake of cleaning their bikes upside-down, which allows water to run into the head bearings. The symptom of rusting bearings is as described by zacklaws above; the steering feels stiff after a rest then loosens up when you turn it. This needs urgent remedial action.
 

andrew_s

Guru
Location
Gloucester
It's a wear and tear thing. It will actually happen later on a badly adjusted headset, or one that is used on rougher roads.

Despite the common description ("brinelling"), it isn't the balls making dents in the races due to impact, but is fretting damage due to continuous micro-movement in the same place.
Because the steering is usually set in one position (forwards), the grease gets squeezed out from between the balls and the races. The balls and the races micro-weld to each other where the lumpy bits on the surfaces touch, and then when the bearing does move, the micro-welds tear.

If you've got traditional cup and cone style bearings, you can make things last longer by swapping caged bearings for loose balls
 

Globalti

Legendary Member
I have always believed that if your head bearing is correctly adjusted, the load will be shared more or less equally between all the balls but as soon as you allow movement the effect explained above takes place with resulting wear on the most stressed balls and areas of the races, i.e. those in the fore and aft orientation.
 
Modern headsets rarely do this, although some threaded designs persist without races that can move relative to the pressed-in cups.

You need to look for a headset where either the bearings are cartridges that sit in the cups OR there are separate races either side of the bearing cage, a la Stronglight A9. Either of these options allows fore-and-aft rocking motion to be accommodated by the races moving against the cups rather than by the balls/needles themselves. Generally, A-head designs are OK because their introduction happened to coincide with the "indexing" problem being finally understood.
 

Tynan

Veteran
Location
e4
hmm

of late I get a distinct but minor kinda click from somewhere when I brake hard on the front, and if I'm really giving it some and putting a bit og heave on the bars, from that I
m guessing it the headset area, the bike has had at least one hard smack from immediately in front of it, it's two years old, might that be some sort of minor wear/tear to a bearing?

no other symtpms at all, just the noise, quiet but distinct
 
Top Bottom