Four decades on one problem: motorcycle cylinders that fit right, run clean and last. Cast iron, aluminium alloy, ceramic-plated bores and big bore kits — 190 active part numbers shipping to the US, Japan and Europe.
Started in Anding, Tainan — cylinders and engine components only.
Scooter, underbone and two-stroke platforms — every spec published and comparable.
Yamaha, Honda, Suzuki, SYM, KYMCO, Piaggio, Aprilia, Kawasaki, Peugeot, Derbi, Minarelli.
Aftermarket and performance channels across the US, Japan, Europe, Asia and Latin America.
A same-size service replacement and a kit that takes a 125 to 155cc go through the identical measurement routine before they ship.
A ceramic-plated bore replaces the conventional cast-iron liner: heat leaves the wall faster, the wall itself is thinner, and the same outside diameter yields a larger bore. Suited to high-revving and liquid-cooled platforms.
More displacement from a larger bore, with the crank stroke left alone. Each kit ships as a complete top end: cylinder, piston, rings, wrist pin and gaskets.
Cylinders and big bore kits for Cygnus, Majesty, Jog, RS and related scooter and underbone platforms.
Wave, CG-series and scooter platforms — service sizes and oversize bores supplied side by side.
FIG. 01 Bore · Stroke · Displacement
Every part number publishes its bore, stroke and displacement, so a distributor can match it against a customer's engine before ordering. Four decades in the aftermarket taught us the obvious: a return costs far more than one more measurement.
| Original size | ø37 × 46 mm — 49.5 cc |
|---|---|
| Big bore size | ø47 × 46 mm — 79.8 cc |
| Displacement gain | +30.3 cc (+61.2%) |
EXAMPLE · SYM MIO 50
Four gates. Every one leaves a measurement record.
Cast iron or aluminium alloy, chosen per part number. Incoming stock is checked for structure and hardness first — a batch that reads wrong never enters the line.
Rough bore, finish bore, hone. The crosshatch angle is held constant so the rings seat properly during break-in.
Ceramic parts are plated at this stage; cast-iron parts have their liners pressed and re-machined so concentricity holds.
Bore, roundness and surface finish are gauged piece by piece. What passes is kitted with its piston, rings, pin and gaskets and boxed as one assembly.
Newly developed scooter-platform big bore kits and ceramic-plated cylinders on the stand, with fitment consultation available.
Bore, stroke and displacement for all 190 active part numbers are now online so distributors can verify fitment directly on the site.
Additional ceramic-plated part numbers for liquid-cooled scooter platforms, improving both heat rejection and wear resistance.
Send us the model or the engine details — we usually reply within one working day. OEM / ODM enquiries welcome.