Complete CB125 Front Suspension Parts List for Restoration and Repair

If you’re restoring or repairing a Honda CB125, understanding the front suspension parts is essential for a safe and functional ride. The CB125, produced from the 1970s through the 1980s, features a simple telescopic fork setup, but sourcing the correct parts can be tricky. This guide covers every component you’ll likely need, from the fork tubes to the steering stem bearings, with practical advice on what to look for when buying replacements.

Front Fork Assembly Overview

The CB125 front suspension consists of a pair of telescopic forks, each comprising an outer tube (stanchion), an inner tube (slider), springs, damping rods, seals, and bushings. The assembly is held together by the triple tree (upper and lower yoke) and steering stem. Below is a detailed breakdown of each part.

Fork Tubes (Stanchions)

The fork tubes are the outer chrome-plated tubes that slide inside the lower legs. They are prone to pitting and rust, especially if the bike was stored outdoors. For the CB125, the fork tube diameter is typically 27mm, but always verify your model year. OEM replacements are available from Honda, but aftermarket options from brands like All Balls or Tusk are common. When buying, check for straightness and surface condition. Slight pitting can be polished, but deep pits will damage seals.

Fork Sliders (Lower Legs)

The lower legs, also called sliders, house the damping rod and spring. They usually have a cast aluminum construction with a lug for the axle and fender. On the CB125, the right slider often has a brake caliper mount. These parts can crack or get bent in a crash. Aftermarket sliders are rare, so you may need to find used OEM parts in good shape. Ensure the axle hole is not ovalized and the brake mount threads are intact.

Damping Rods

The damping rods sit inside the fork sliders and control rebound and compression damping through orifices. On older CB125s, the design is simple—a metal rod with holes. They rarely wear out but can become clogged with old oil. If you’re rebuilding, clean them thoroughly. Aftermarket performance damping rods are not common for the CB125, so stick with OEM or clean originals.

Fork Springs

The springs provide the suspension’s spring rate. Over time, they can sag and lose tension. OEM springs are progressive or straight-rate depending on the model year. Aftermarket springs from companies like Progressive Suspension or Hagon are available and often improve ride quality. When ordering, specify your CB125’s year and whether you want standard or heavier springs for carrying loads.

Fork Seals

Fork seals prevent oil from leaking out and dirt from getting in. The CB125 uses a standard 27mm seal size (27 x 40 x 10.5). Always replace seals in pairs. OEM seals are good, but aftermarket seals from All Balls or SKF are equally reliable and often cheaper. Never reuse old seals; they are the most common cause of fork oil leaks.

Dust Wipers

Dust wipers sit above the seals and keep debris off the fork tubes. They are cheap and should be replaced with every seal change. The part number is often included in seal kits. If you cannot find them separately, a universal dust wiper of the correct inner diameter (27mm) will work.

Fork Bushings

Inside the slider, there are two bushings per fork leg: one at the bottom and one at the top. They guide the slider on the tube. Worn bushings cause a loose, clunky feel. The CB125 uses a 27mm bushing set. Replace them if there is noticeable play or if the fork oil looked metallic. Aftermarket kits are available.

Fork Oil

Not a part per se, but essential. The CB125 typically uses 10W or 15W fork oil. Each fork leg holds about 150-170 ml. Use a quality brand like Bel-Ray or Motul. Overfilling can cause harshness; underfilling leads to poor damping. Check your service manual for the exact air gap or volume.

Triple Tree and Steering Stem

The triple tree (upper and lower yoke) holds the fork tubes to the frame and allows steering. It includes the steering stem, bearings, and stem nut.

Upper and Lower Yokes

The yokes are cast aluminum or steel. The CB125 has a simple design with two pinch bolts per fork tube. They rarely fail unless bent in a crash. Check for straightness by looking at the fork tube alignment. Aftermarket yokes are rare; stick with OEM or used parts.

Steering Stem Bearings

The steering stem rotates on ball bearings or tapered roller bearings. The CB125 originally used loose ball bearings (steering head bearings). Many owners upgrade to tapered roller bearings from All Balls for smoother steering. You’ll need the steering stem nut, dust seal, and bearing races. This upgrade is recommended for better handling.

Splined Steering Stem

The steering stem is a long shaft that goes through the frame neck. On the CB125, it’s often splined at the top for the handlebar mount. Rust can cause stiffness. If you have a crashed bike, inspect the stem for bending. Replacement stems are available used; new OEM parts are discontinued but sometimes still found.

Other Front Suspension Components

Axle and Spacers

The front axle holds the wheel between the fork sliders. The CB125 uses a 12mm or 14mm axle (varies by year). Spacers on each side center the wheel. These are often lost during disassembly. Measure your old ones and order replacements from Honda or a fastener supplier. Stainless steel aftermarket axles are an upgrade.

Axle Nut and Cotter Pin

The axle nut is a castle nut secured with a cotter pin. Always replace the cotter pin. Nuts are standard M12 or M14 with fine thread.

Front Fender Mounts

The fender bolts to the fork sliders with two bolts on each side. These bolts can strip. Use the correct size (usually M6 or M8) and a thread locker. Aftermarket aluminum fenders may require different mounts.

Brake Caliper Bracket

If your CB125 has a front disc brake, the caliper bracket attaches to the right fork slider. This bracket can warp, causing brake drag. Check it for flatness. Replace if damaged.

Where to Find CB125 Front Suspension Parts

While we don’t promote specific marketplaces, you have several options. OEM Honda parts are ideal but discontinued for many models. Check your local Honda dealer for remaining stock. Aftermarket suppliers like All Balls Racing, Tusk, and Emgo (through distributors) offer seals, bushings, bearings, and springs. For discontinued items like fork tubes, look for used parts from salvage yards or online communities dedicated to vintage Honda bikes. Avoid parts from unknown brands; stick with reputable manufacturers. For rare parts, consider upgrading to aftermarket components that fit with modifications.

Final Recommendation

Start by inspecting your current suspension. Write down the condition of each part. Always replace seals, bushings, and dust wipers together—these are cheap and critical. Invest in good fork oil and clean the damping rods thoroughly. For the steering stem, upgrade to tapered roller bearings—they improve handling and are easy to install. If your fork tubes are pitted, try polishing light rust; if deep, replace them. For springs, aftermarket options are a worthwhile upgrade if you want better ride quality. Keep all original hardware and spacers; if missing, measure carefully and order proper replacements. With this parts list and a methodical approach, you’ll have a front suspension that works reliably for years.