Valve Adjustment Kit | Honda CB175 / CB200
Valve adjusters rarely go missing on these bikes, but after fifty years they get worn and pitted. A pitted adjuster face or a lock nut that will not hold is how a clearance you just set drifts back out on the ride home.
Why You Need This
The adjuster screw sets the gap between the rocker arm and the valve stem, and the lock nut holds that gap where you put it. Once the face is pitted or the threads are tired, the setting moves. Too tight is what does damage; too loose only makes noise.
We set these every 1,500 miles (2,400 km) as part of the standard tune-up. The order matters, because each step feeds the next: oil change, then cam chain, then valves, then ignition timing.
Specifications
| Spec | Detail |
|---|
| Replaces OEM Parts | 90012-333-000 (adjuster screw), 90206-KM3-000 (lock nut) |
| Fits Models | CB175 K0 (1968), K3 (1969), K4 (1970), K5 (1971), K6 (1972), K7 (1973); CL175 K0, K3–K7 (1968–1973); SL175 K0 (1970), K1 (1971–1972); CB200 K0 (1973–1974), CB200T (1975–1976); CL200 (1974) |
| Sold As | Sold Individually — one adjuster screw with its lock nut |
How many you need: these engines have four valves, so four adjusters. Each unit here is one screw with its nut, so a complete set is four.
Valve Clearance Specs
Intake and exhaust run the same number on this family, set cold.
Installation
Difficulty: Intermediate
Tools needed: 3mm / 4mm square-head valve adjustment wrench, 8mm box wrench for the lock nut, feeler gauge
- Start cold. Pull the spark plugs, the tappet hole caps and the stator cover.
- Turn the crankshaft until the T mark lines up with the index mark on the stator, with that cylinder on its compression stroke. A finger over the plug hole tells you which stroke you are on — you will feel the air push out.
- Slide the feeler gauge between the rocker arm tip and the top of the valve stem.
- Break the lock nut loose with the 8mm wrench. The adjuster underneath has a square head, which is what the 3mm / 4mm wrench is for.
- Set the gap, then tighten the lock nut while holding the adjuster still. If the adjuster turns as the nut goes tight, the setting is gone.
- Re-check the gap once the nut is tight, then rotate the crankshaft 360 degrees and do the other cylinder.
Why a full turn between cylinders. The CB175 and CB200 use a 360-degree crankshaft, so both pistons rise and fall together. That is different from the 350, 360 and 450 twins, and it is why you go a full rotation rather than half.
The trick we use: rather than chasing a perfect 0.002 in. slip fit, set a 0.003 in. blade snug and err loose. If the gauge will not pull back out it is too tight; if it goes in with no drag at all it is too loose.
The video runs the cam chain and valve adjustment end to end on this engine family.
Frequently Asked Questions
How many do I need to order?
Four. These engines have four valves, two intake and two exhaust, and each one has its own adjuster. Every unit here is one adjuster screw with its lock nut.
What clearance should I set?
0.05 mm (0.002 in.) on both intake and exhaust, engine cold. This family runs the same number on both sides.
What wrench sizes do I need?
An 8mm box wrench for the lock nut, and a 3mm / 4mm square-head wrench for the adjuster itself. The adjuster head is square rather than slotted, so a screwdriver will not hold it. We sell the CT90 / CB175 / CB200 valve adjustment wrench separately, and you can add one to this order with the checkbox above.
Do the CB350 valve covers fit my CB175?
No. Our valve covers fit the 350, 360 and 550 engine families, not the 175 or 200, and we do not currently stock a cover for this one.
My clearance changed after I tightened the lock nut. What happened?
The adjuster turned with the nut. Hold it still with the square-head wrench while you snug the lock nut, then re-check the gap before rotating to the next cylinder.
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Last updated: August 2026
