Honda CM450A Hondamatic Parts & Accessories

Honda CM450A Hondamatic Parts & Accessories

Honda's CM series brought the parallel-twin engine format into a comfortable, approachable cruiser package that appealed to new riders and experienced commuters alike. The Honda CM450A Hondamatic runs a 449cc SOHC parallel-twin with Hondamatic automatic transmission in a low-seat chassis that eliminates the clutch lever entirely. The Hondamatic gearbox made this one of the most accessible larger-displacement motorcycles Honda ever built, attracting riders who preferred automatic operation for urban commuting. Riders keeping this machine on the road need carb hardware, drivetrain consumables, and chassis components that match OEM specifications.

Popular Upgrades

Frequently ordered parts for the CM series include Keyster carburetor rebuild kits, Barnett clutch friction plates and springs, NGK spark plugs, Emgo exhaust pipes and heat shields, fork seals, drive chain and sprocket sets, and Yuasa batteries. Barnett clutch kits provide better engagement feel than worn OEM plates. NGK plugs in the correct heat range keep combustion clean and prevent fouling on low-mileage runs.

Performance and Handling

The CM series front forks use conventional oil-damped tubes that benefit from fresh seal sets and oil every 20,000 miles or two years. Rear shocks can be replaced with aftermarket units at the correct extended and compressed lengths to maintain the CM's relaxed riding geometry. Drive chain stretch accelerates sprocket wear rapidly, so replacing chain and front and rear sprockets as a matched set is the most cost-effective maintenance approach. The drum or disc brake hardware is straightforward and responds well to fresh pads or shoes.

What carburetor kit fits a Honda CM450A Hondamatic?

The CM450A uses dual Keihin CV carbs. Keyster rebuild kits cover both carbs in the set with correct jets, needles, float valves, and gaskets. The Hondamatic transmission is lubricated by the engine oil, so keeping the engine well-maintained directly affects transmission longevity.

What clutch kit fits a Honda CM series?

Honda CM parallel-twins use a wet multi-plate clutch. Barnett clutch kits sized to the CM displacement include the correct number of friction plates and steel plates with the right thickness and OD. A fresh clutch spring set is always recommended alongside new plates to restore full clamping pressure and eliminate slippage under hard acceleration.

Why These Parts Fit Right

Parts are listed with the specific CM variant and model year required for accurate fitment. The Hondamatic automatic transmission is specific to A-suffix CM models and requires different internal service parts than manual variants. OEM-equivalent specifications mean installation requires only basic tools.

CM owners interested in related content can browse the exhaust systems collection, the suspension catalog for fork and shock upgrades, or explore air intake upgrades available for other Honda models.