Kitaco 88cc BIG Bore-Up Kit suitable for use with Z50J 12V, ST50 Dax 12V

Kitaco 88cc STD Big Bore Kit with Aluminum Cylinder (Part No. 214-1083102)

This kit is compatible with the following Honda models and frame number ranges:

• Monkey / Gorilla: Z50J-2000001～ and AB27-1000001～1899999
• Monkey Baja: Z50J-1700001～
• Dax 50 (12V): AB26
• Jazz: AC09
• Magna 50: AC13
• Chaly 50: CF50-3400001～
• CD50 / Benly 50S / Benly CL50: CD50-1500001～
• Super Cub 50 and variants (including Press Cub, Little Cub, Giorcub): Various C50 and AA01 frame ranges
• Solo: AC17
• XR50R / CRF50F: AE03

Note: For Monkey R/RT (AB22) models, the Kitaco Rocker Arm Set is required separately. This is the without high camshaft version.

This reliable 88cc STD Big Bore Kit from Kitaco is designed for later-model Honda Monkey, Gorilla, Dax, Chaly, Cub, and compatible 50cc engines. It provides strong, usable power and torque gains across the entire RPM range while maintaining excellent street manners and reliability for daily riding.

Kit Contents & Performance Features

The kit includes a new STD-type cylinder head with an optimized combustion chamber, high-efficiency port shapes, larger valves, and a high-compression cast piston. These upgrades significantly improve airflow and combustion efficiency, delivering noticeably stronger performance than a stock engine across low, mid, and high RPMs.

Key specifications:

• Displacement: 88cc
• Bore: φ52mm
• Stroke: 41.4mm (uses stock crankshaft)
• Valves pre-installed in the cylinder head
• High-compression cast piston
• Aluminum cylinder (standard version)

Cylinder Construction: Aluminum with Cast Iron Sleeve

This version features Kitaco’s standard aluminum cylinder with a cast iron sleeve inserted into the bore. This is a proven, cost-effective design widely used in performance upgrades.

Benefits of the Aluminum + Cast Iron Sleeve Cylinder:

• Excellent durability: The cast iron sleeve provides a hard, wear-resistant surface that stands up well to the piston rings, offering reliable long-term performance in a big bore setup.
• Good heat management: The aluminum outer cylinder helps with heat dissipation while the iron sleeve maintains excellent strength and stability under operating temperatures.
• Proven reliability: This traditional sleeved design has a strong track record in Honda Monkey-family engines and is ideal for riders seeking solid performance gains at a great value.
• Lightweight advantage: The aluminum construction keeps overall weight in check compared to older fully cast iron cylinders.

This kit is an outstanding choice for enthusiasts looking for a meaningful power increase with dependable everyday usability. For even smoother power delivery, a high camshaft can be added separately. We recommend using high-quality engine oil, proper carburetor jetting, and following proper break-in procedures. Professional installation is advised, and always verify exact compatibility with your specific model and year.