Maxima Fork Oil (1L)

Description

Maxima Fork Oil for Vintage Honda Motorcycles

Fork oil is the fluid your front suspension pushes through to control how it compresses and rebounds. As it ages it breaks down and foams, your damping fades, and the front end starts to feel harsh and uncontrolled. This is fresh Maxima fork oil in 10WT and 15WT, the grades that cover the whole vintage Honda range.

Why You Need This

A fork-oil change is one of the cheapest, biggest improvements you can make to how an old Honda rides. Old oil loses its damping and lets the fork foam, so the front end packs down over bumps and dives under braking. Fresh oil brings the damping back. Maxima’s Lubricinol additive package fights that foaming and conditions the fork seals as you ride, so the seals stay supple and leak later.

About Maxima Fork Oil

• Mineral-based fork oil built for the standard telescopic forks on vintage Honda front ends
• Lubricinol-fortified additive system — minimizes foaming and conditions the fork seals
• Offered in two weights, 10WT and 15WT (see below to choose)
• 1 Liter (33.8 oz) bottle — enough oil to do two complete sets of forks

Which Weight: 10WT or 15WT?

From the factory these forks were filled with ATF — roughly a 5-weight oil. Maxima’s 10WT and 15WT are a step up from there, and you pick between them by rider weight and how you ride:

• 10WT — the right choice for most riders under about 200 lb, on normal roads.
• 15WT — more damping for heavier riders, or for rougher roads where you want a firmer, more controlled front end.

Both weights fit every model below — the weight is about feel, not fitment.

Specifications

Spec	Detail
Type	Mineral-based motorcycle fork oil (Lubricinol anti-foam additive)
Weights	10WT or 15WT (choose by rider weight)
Volume	1 Liter (33.8 oz) — does two sets of forks
Factory Fill	Honda originally specified ATF (about a 5-weight)
Fits Models	Vintage Honda telescopic forks — CT90, CB100/CL100/SL100, CB125/CL125/SL125, CB175/CL175/SL175, CB200/CL200, CB350/CL350/SL350, CB360/CL360/CJ360, CB450/CL450/CB500T, CB500K/CB550K/CB550F, CB750
Sold As	Individually (1 Liter bottle)

How Much Fork Oil Does My Bike Need?

These are approximate amounts per fork leg for an oil change. Always measure the exact volume with a graduated cylinder — an under- or over-filled fork damps poorly. On several models the amount changed across the years as the fork design changed, so match your exact variant:

Model	Per Fork Leg (approx.)
CT90 / Trail 90	120–140 cc
CB175 / CL175	135–145 cc
SL175	175–185 cc
CB200 / CL200	115–130 cc
CB350 / CL350 — early (external spring)	~200 cc
CB350 / CL350 — late (internal spring)	135–140 cc
SL350	180–190 cc
CB360 / CL360 / CJ360	135–140 cc
CB450 / CL450 (K0–K2, 1965–69)	~290 cc
CB450 / CL450 (K3–K4, 1970–71)	~225 cc
CB450 / CL450 (K5, 1972)	~160 cc
CB450 (K6–K7, 1973–74)	~140 cc
CB500T	~140 cc
CB500K (CB500 Four)	~160 cc
CB550K / CB550F	165–170 cc (oil change) · 185–190 cc (full rebuild)

The early CB350/CL350 forks carry the spring outside the tube; the later ones moved it inside, and the fill amount dropped a lot — so confirm which you have before you measure. (Also fits the CB100/CL100/SL100, CB125/CL125/SL125 singles, and CB750 — we don’t publish a per-leg figure for those yet, so measure your fill carefully.)

Installation

Difficulty: Beginner

On most of these bikes you can change the oil with the forks on the bike:

1. Loosen the fork top cap before you lift the wheel (it’s easier with the fork compressed).
2. Pull the drain screw at the bottom of the fork leg and let it drain, then work the fork up and down to pump out the rest.
3. Reinstall the drain screw, then pour in your measured amount of fresh oil through the top.
4. Reinstall the top cap, and repeat on the other leg.

We walk through the whole job in our fork-oil-change video: