TAIDA 172cc 61mm BIG BORE KIT – 61mm BORE – 62.7mm OD

High-performance TAIDA big bore kit designed as a special DROP-IN upgrade for compatible GY6 125cc/150cc A-Block engines with 54mm cylinder stud spacing.

This kit combines a 61mm TAIDA cast-iron cylinder and cast-aluminum piston with a performance 28mm/23mm big-valve cylinder head. The special 62.7mm outer cylinder sleeve is designed to fit compatible stock 54mm GY6 A-Block cases without boring or case machining.

DISPLACEMENT

• 61mm Cylinder Bore
  • Approximately 171cc / 172cc depending on crankshaft stroke and engine configuration
  • Commonly marketed as a TAIDA 172cc Big Bore Kit
  • Final displacement is determined by both cylinder bore and crankshaft stroke

IMPORTANT FITMENT

• Fits compatible GY6 125cc/150cc A-Block engines
  • 54mm cylinder stud spacing ONLY
  • Compatible with many 152QMI / 157QMJ / 1P57QMJ and similar GY6 engines
  • WILL NOT fit 57mm B-Block engines
  • WILL NOT fit 161QMK, QMK or newer GY7-style 200cc engines
  • WILL NOT fit Genuine Buddy 125
  • Primarily designed for scooter-style GY6 engines; some go-kart and buggy applications may differ
  • Verify your engine code, stud spacing and dimensions before ordering

CYLINDER SPECIFICATIONS

• Bore: 61mm
  • Outer Cylinder Sleeve Diameter: 62.7mm
  • Cylinder Height Without Sleeve: 69.3mm
  • Overall Height With Sleeve: 90mm
  • Cylinder Material: Cast Iron
  • Piston: Cast Aluminum
  • Piston Rings: 1mm / 1mm / 2mm
  • Wrist Pin: 48.5mm x 15mm
  • Stud Spacing: 54mm GY6 A-Block
  • Made in Taiwan

PERFORMANCE CYLINDER HEAD

• TAIDA 2-Valve Performance Head
  • 54mm Stud Spacing
  • 28mm Intake Valve
  • 23mm Exhaust Valve
  • 5mm Valve Stems
  • Intake Port: 26.5mm
  • Exhaust Port: 25mm
  • Intake Manifold Opening: 28mm ID
  • Oversized valve ports for increased-performance applications

KIT INCLUDES

• TAIDA 61mm Cast-Iron Cylinder
  • 61mm Cast-Aluminum Piston
  • Piston Rings
  • Wrist Pin & Circlips
  • TAIDA 28mm/23mm Cylinder Head with Valves Installed
  • 8mm Studs & Hardware
  • Head Gasket
  • High & Low Compression Base Gaskets
  • Chain Tensioner Gasket
  • Intake Manifold Spacer & Gasket
  • Exhaust Gasket
  • Intake & Exhaust Studs / Nuts
  • TAIDA Sticker

PLEASE NOTE: Depending on the production batch, the piston may arrive installed in the cylinder or packaged separately for installation.

SPECIAL DROP-IN DESIGN

This is the special 62.7mm OD version designed as a NO-BORING / DROP-IN kit for compatible stock GY6 A-Block engines with 54mm stud spacing.

Most other large-bore cylinders use a larger outer sleeve diameter. This TAIDA cylinder uses a 62.7mm OD sleeve specifically intended to fit compatible 54mm A-Block cases without boring.

Engine variations do exist. Always confirm that you have a genuine GY6 A-Block configuration with 54mm stud spacing before installation.

TUNING & INSTALLATION

Increasing engine displacement requires proper fuel-system tuning. Carbureted engines will generally require re-jetting after installation.

For performance applications, a properly tuned 26mm or 30mm CVK-style carburetor with accelerator pump may be considered. Correct jetting depends on the carburetor, intake, exhaust, elevation and other engine modifications.

PROFESSIONAL INSTALLATION STRONGLY RECOMMENDED

This is an aftermarket high-performance engine component and should be installed by a qualified professional mechanic.

Proper assembly, timing, valve and piston clearances, fuel mixture, break-in and engine tuning must be checked during installation.

IMPORTANT AFTERMARKET PERFORMANCE PART NOTICE

• NO WARRANTY on aftermarket performance parts
  • Professional installation is strongly recommended
  • Improper installation or tuning can result in engine damage
  • TAIDA designs, finishes, markings, packaging and component appearance may change depending on production date and order date
  • Stock photos are for reference; the product received may have minor design or appearance differences while serving the same intended application

OFF-ROAD USE NOTICE