Park Tool biodegradable chain degreaser & bike cleaner 16 fl oz — plant-based, safe for drivetrain

Park Tool CB-4 Bio ChainBrite is a 100% biodegradable, plant-based degreaser formulated to dissolve grease and grime from bicycle chains and components without harsh solvents. Park Tool CB-4 cleans drivetrain parts, derailleurs, cassettes, chainrings and other bike components while using plant-derived ingredients that break down naturally. Packaged in a 16 fl oz (472 ml) bottle with a flip-top cap, this formula is designed for home mechanics who want an effective, environmentally friendlier alternative to solvent-based cleaners. Regular cleaning with CB-4 helps keep parts free of abrasive grit and extends the effective life of lubricants and shifting components when paired with proper lubrication.

How quickly does CB-4 remove heavy grease and grime?

CB-4 targets sticky, baked-on grease and everyday road or trail dirt through a concentrated plant-based solvent blend. It loosens contaminants for fast rinsing or wiping, cutting down the time you spend scrubbing metal surfaces.

• Formulated to penetrate and lift oil and grime from chains and cassettes.
• Works on derailleurs, chainrings, bottom brackets (external), and pedals.
• Reduces need for aggressive mechanical scrubbing in most cleaning jobs.

Is this safe for bike finishes and seals?

CB-4 uses natural, biodegradable agents that are less aggressive than many petroleum-based degreasers, making it suitable for routine bike cleaning. As with any cleaner, avoid prolonged contact with painted decals and sensitive seals; test in a small area if unsure.

• Plant-based formulation minimizes harsh solvent exposure to paint and anodized surfaces.
• Avoid soaking foam grips, leather saddles, and vulnerable rubber seals for extended periods.
• Rinse or wipe off within minutes to protect finishes and components.

How should I use CB-4 for best drivetrain results?

Apply CB-4 directly to the chain and components, allow a short dwell time to loosen grime, then agitate with a brush or chain-cleaning tool. Rinse or wipe thoroughly and allow parts to dry before applying a quality chain lubricant to restore smooth shifting.

• Use the flip-top lid for controlled pouring into chain-cleaner tool reservoirs or onto brushes.
• For heavy buildup, repeat application and agitate with a stiff nylon brush.
• Always relubricate chain after cleaning to prevent corrosion and wear.

What makes CB-4 a greener cleaning choice?

CB-4 is based on biodegradable, plant-derived ingredients rather than petroleum solvents, so it breaks down more readily in the environment. Its formulation balances cleaning performance with a reduced ecological footprint compared with conventional degreasers.

• 100% biodegradable and plant-based surfactants and solvents.
• Designed to replace harsher solvent cleaners for regular bike maintenance.
• Concentrated enough for effective cleaning from a single 16 fl oz bottle for multiple uses.

Who is this for? CB-4 Bio ChainBrite is intended for cyclists, home mechanics and shop technicians who want an effective drivetrain degreaser that favors biodegradable chemistry. It suits road, gravel and mountain bikers who perform regular maintenance and prefer a cleaner that removes heavy grime while being easier on the environment than many solvent-based alternatives. Combine CB-4 cleaning with a quality chain lubricant and routine maintenance to keep gears shifting smoothly and to reduce abrasive wear on drivetrain parts.

FAQ

Q: Can I use CB-4 on suspension parts and bearings?

A: Avoid soaking internal bearings or suspension internals; use CB-4 for external surfaces and wipe off promptly to prevent seal swelling.

Q: Do I need to rinse after using CB-4?

A: Rinse or thoroughly wipe parts after cleaning, then dry and apply lubricant to protect the drivetrain and prevent corrosion.