2-4 hours if you have everything you need for the job (parts and tools). Repack even the new bearings with grease, if they are not sealed. I pick out the seals and repack them anyway, and put the seals back on. I use a seal pick, which is like a dentists probe but you can probably find something to do the job.

Watch out for over or under tightening of the steering head when you re-assemble. It's best to slightly (very slightly! It may even be well less than 1/8th of a turn) over-tighten so you feel the head bind a little as you move it though it's full travel left to right. Then you know to back it off until it is completely free, but has no slop. Over-tightening also makes the bearing seat properly so it doesn't loosen up on the first ride. Leaving slightly over-tight will make the bike "wander" as you ride, which, if the bearings are shot now is probably what is happening as well. It will also make the bearings wear faster. Under-tight will make the front end "chatter" or clunk under braking.

Do you know how to check for under or over tight? See the reference to binding above for over-tight. To check for under-tight, prop the bike up so the front is off the ground and grab the fork legs at the bottom. Standing in front of the bike, pull the fork legs carefully back and forwards. There should be no play. If there is play (slop or movement) see if it's at the point were the fork leg and slider meet (fork bushes inside the sliders are worn, not common). If it's not there, then is must be at the top in the bearings. Tighten a little at a time and check to see if the play reduces.

Sometimes the amount of play also reduces when you do up the big locking nut, making it over-tight when you think you have got it right. In this case, leave the bearing very slightly loose. The final nip-up of the big lock nut will take up the last of the slack.

It sounds complicated, but it's all pretty logical once you get into it. An extra 10 minutes getting the tension right can double the life of your steering head bearings. Checking the bearings with the front off the ground is something I do every 3-4,000km. They also need to be re-greased. It's a job that should be done every 15,000km or so to get the best life from the bearings.

Feel free to ask me for help, via here of PM.

Kind regards

Nigel in NZ

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