Tapered Roller Steering Bearings | Honda CB500K / CB550K / CB550F

Tapered Roller Steering Bearings | Honda CB500K / CB550K / CB550F

The steering head on your four-cylinder Honda turns on loose steel balls packed in grease between two cone races. This kit replaces that arrangement with sealed tapered roller bearings, upper and lower, and it is the last time you will need to open the headset.

Why You Need This

Honda assembled these bikes with 18 steel balls in the upper race and 19 in the lower cone. Nothing retains them. They work, and they worked for a long time, but the original bearings in most of these bikes have never been serviced since they left the factory. Fifty years of weather and road grit later they go rusty, pitted, or packed with dirt, and the steering gets heavy.

The wear concentrates where the bike sits. A parked motorcycle points straight ahead, so that is where the races take the load, and that is where you feel it first — a catch or a detent as you turn off center. Tapered rollers carry the same load across a cone-shaped race instead of a row of points, and because the rollers are held in a cage, the bearing stays assembled in your hand instead of scattering across the bench.

Specifications

Model-Specific Notes

• CB750K, CB750F Super Sport, CB750A: this is the correct kit. The same bearing set covers the four-cylinder range from the CB500K through the CB750, and CB750 fitment is listed on this product's own compatibility chart.
• CB500K and CB550: the kit is shared across the whole CB350-through-CB750 family. We list it under four separate SKUs, one per model group, so each page is easier to find. The physical part is identical on all four.

What's in the Kit

• Upper and lower tapered roller bearings
• Upper and lower bearing races
• Dust seals
• Shim washers

Note: the shim you need depends on the bike. Check the instructions against your machine before you drive anything on.

Installation

Difficulty: Intermediate

Tools needed: 48 mm pin spanner (Honda tool no. 07902-200000), 30 mm socket or a good adjustable wrench for the stem nut, brass hammer, brass punch, a hollow driver or a length of pipe sized to the bearing's inner race, and automotive wheel bearing grease.

1. Strip the front end down to the upper and lower triple trees, then turn the triple tree against the frame stop so you have something to work against.
2. Take off the stem nut and lift the upper triple tree away. Back the notched adjuster nut off with the pin spanner, holding the lower triple tree as it comes free — the steel balls drop out as soon as it releases.
3. Drive the old races out of the frame with a brass punch, working around the edge so they come out square. Start with the lower race; it is the easier of the two.
4. Drive the pressed-on lower race off the steering stem. This is the hardest part of the job, so be patient. The old shim and rubber seal will not survive it.
5. Wash the head pipe and inspect it. Check the stem for twisting or cracks, the cone race for wear, and the frame stop for damage.
6. Chill the new races in the freezer before you fit them. Cold, they go in almost by hand. Drive them home with the brass hammer and check with a thumbnail that no gap remains between the race edge and the frame.
7. Pack both bearings by hand. Work the grease through the rollers until it squeezes out of the top side, then grease the installed races as well.
8. Fit the lower stack in order — shim, then dust seal with the flat side down and the lip facing up, then the bearing. Drive only on the bearing's inner race. Striking the cage will bend and ruin it.
9. Set the stem into the head pipe, fit the upper bearing and dust cap, and thread the adjuster nut down. Snug it until you feel it touch, then back it off a hair. You are aiming for smooth rotation with no play at all — too tight and the bars are hard to turn, too loose and the front end wanders.
10. Refit the fork tubes before you finally tighten the top nut, so the upper and lower triple trees stay aligned. Torque the steering stem nut to 8.0–12.0 kg-m (57.9–86.7 lb-ft).

The upper bearing has the smaller inner diameter and the lower has the larger one. The dust seals follow the same logic. Lay them out before you start and you will not have to guess halfway through.

Expect to reset the preload after your first ride. New bearings settle, and the slack that appears is normal. Give the adjuster a gentle nip up and re-check.

Our two-part steering bearing series walks the whole job, teardown in part one and installation in part two.

Frequently Asked Questions

Does this fit the Honda CB750?

Yes. CB750K (1969–1978), CB750F Super Sport (1975–1978) and CB750A (1976–1978) are all listed on this kit's compatibility chart. The same bearing set covers the CB350 through the CB750.

Does one kit do both the top and the bottom?

Yes. One kit is a complete set: upper and lower bearings, both races, dust seals and shim washers. You do not need to order two.

How do I tell which bearing goes on top?

By the inner diameter. The upper bearing is the smaller of the two and the lower is the larger. The dust seals match the same pattern.

The top race sits slightly proud of the frame when it is fully seated. Is that right?

Yes, that is normal on these bikes. The top bearing race protrudes above the neck by roughly 3 mm once it is home.

My steering feels looser a week after fitting them. Did I do something wrong?

Almost certainly not. Tapered rollers bed in over the first few miles and take up the slack left during assembly. Re-set the preload with the pin spanner once the bike has been ridden, and it should stay put after that.

Do I need special tools?

A pin spanner is the one item most people do not already own. Honda's own tool for this is a 48 mm pin spanner, no. 07902-200000. Beyond that a brass hammer and punch, a driver or pipe sized to the inner race, and wheel bearing grease will see the job through.

You Might Also Need

• Fork Seals (EZ Install) | Honda CB450 / CB500 / CB550 — the forks are already out to reach the steering head
• Front Wheel Bearing & Seal Kit (Disc Brake) — the other bearing set worth checking when the front end is apart
• Fork Boots (Gaiters) | Honda CB450 / CL450 / CB550 / CL350 — same teardown, and the old ones are usually perished
• Factory-Style Rear Shocks | Honda CB350 / CB360 / CB450 / CB550 — if the front end is getting attention, the back usually needs it too

Last updated: September 2026