Integrated Headset (& Bearing) Replacement - Mountain mtb or Road Bike

How to easily replace a mountain bike mtb or road bike headset or just the headset bearings (https://www.firstcomponents.com/heads....

The first thing to do is to clear the forks of any cables or levers. You have to remove the forks so they need to be completely un-attached to the bike by any cables. The main one here is the brake cable. You don’t have to remove the forks, but you’ll find removing and handling the forks is a lot easier if you do.

The preparation for fork removal involves loosening the stem bolts (or bolt if your bike only has one stem bolt) and top cap tensioner bolt. The top cap bolt holds the fork and headset assemblage together. You should hold the fork to prevent it falling to the floor. Once the top cap is released and the bolt completely clear, the forks can be removed by just sliding them out. The bearings that sit just inside the head tube may come loose like as in the video. If not you may have to gently pry them out with an awl or small screwdriver or even employ a removal tool.

We’ll be replacing all the headset parts here with a completely new headset. The star nut would be useful if installing a new fork. The existing fork will be reinstalled with it’s star nut still in place. Each of the headset components is packed in the box in the in the order each will be installed on the bike. Just lay them out in that order so you can’t go wrong on the installation. The crown race here is fine but may as well be replaced. No special tool is needed to remove it. Just gently lever it up away from the fork crown. If you are just replacing the bearings you won’t need to do this either.

A thin film of grease on the crown race before you install the crown race bearing is a good idea. There’s be no chance of any squeaking should there be any slight movements in times of stress on the trail. Some mechanics generously grease the bearing basically the whole area to completely seal out the water and dirt, a reasonably effective technique, although it can get mighty dirty and indeed act as a dirt magnet. Replacing bearings or the headset as a whole is a quick and easy activity anyway so probably not necessary.

On the install the top-cap should be tight enough to hold everything together, which means it won’t be tight at all. A way to get the right tension is just enough tension so that the spacers don’t move when using a firm grip you attempt to turn them. Any movement here means you need to tighten the tension bolt. However if you have got it tight and the spacers are still loose, this means the gap between the top of the steerer (where it was cut for the original installation and assembly) and the top of the stem is not enough—3mm is the optimal distance. If it’s less than 1mm, you won’t be able to pull the headset assembly together.

Line the front wheel up with the stem. Then tighten the stem bolts enough to stop the stem and front wheel from getting out of alignment again. Then you need to apply the correct torque to the stem bolts. Over tightening may damage the thread or the steerer. Not tight enough and they can work loose which is just dangerous. The technique is important. Tightening each side in turn bit by bit is the best way. Once the wrench clicks in at the specified torque do the other side. Tightening that side slightly loosens the opposite side. Once both sides click easily you have reached tolerance.