Progression in mountain bike geometry has lead to slacker head angles on the whole, one cost effective way to further slacken your bike's head angle is to make use of an angle headset. The opposite is also true should you want to steepen your bike's head angle.
Fitting an angled headset typically provides a range of adjustment between 0.5–1.5 degrees.
Here we've fitted a Cane Creek Angleset. This angleset and its ilk use offset cups (one or both) to give your bike a slacker (more stable) or steeper (quicker steering) head angle. Unlike offset bushings, they don’t significantly affect the bottom bracket height, reach or seat angle.
Secure the (clean) bike in a workstand.
Remove the front wheel and detach the front brake lever from the handlebar.
Undo the headset top-cap bolt, loosen the stem’s steerer clamp bolts and slide the fork out of the headset.
Strap/ziptie the bar to the frame.
Push a ‘rocket’ headset removal tool up through the head tube until the splayed end snaps into place.
Check that the end sits flush against the lower headset cup and the tool is central in the tube. Tap it sharply with a mallet until the cup pops out. Repeat on the upper cup.
Grease the concentric upper cup of the angled headset and sit it on the head tube.
Drop a headset press through the cup and tube, then slot the base plate onto the highest notch available.
With the cup straight and central in the press, turn the handle until the cup is flush with the tube.
Flip the bike upside down in the stand.
Grease the offset lower cup and sit it on the head tube.
The ‘-’ should be at the front if you want a slacker head angle. Use the notches on either side of the cup like a gunsight to line it up centrally with the down tube.
Put a mark on the head tube in line with the mark on the cup. This way, you’ll be able to see if the cup twists.
Repeat step 3 on the lower cup, ensuring that it stays centrally aligned with the shaft of the press and that the mark on the cup lines up with the mark on the tube.
Wipe away any excess grease and flip the bike the right way up.
Grease the bearings and gold gimbals. Place the lower one over the fork’s steerer tube, on top of the crown race.
Push the fork up through the head tube and mount the upper gimbal and bearing, then the dust cap.
Add any spacers before slotting the stem back on.
Install the top cap and bolt and preload the headset to the specified torque setting.
Reattach the brake lever to the bar.
Remove the bike from the stand, replace the front wheel, straighten the bar and tighten the stem’s pinch bolts.