Kawasaki Z125 PRO | Bore-up from stock 124cc to 138cc for a significant increase in power and torque! [Takegawa Special Parts]

The Kawasaki Z125 PRO’s displacement remains at 124cc. It delivers over 10 horsepower at the rear wheel (measured by Dynojet)! [Takegawa Special Parts]

Motorcycle parts manufacturer Special Parts Takegawa has released a series of engine tuning kits that are compatible with Kawasaki’s popular 2-stroke leisure model, the Z125 PRO. Here we will introduce an engine kit that allows you to increase power by incorporating high-compression pistons and high camshafts while keeping the displacement at the standard 124cc. REPORT ● KITA Hideaki Special Parts Takegawa http://www.takegawa.co.jp/

https://motor-fan.jp/bikes/article/136124

Kawasaki Z125 PRO (standard)

Kawasaki Z125 PRO Official manufacturer website　https://www.kawasaki-motors.com/ja-jp/motorcycle/z/mini-naked/z125-pro

Is the Kawasaki Z name true? Naked Sports Z125PRO test ride impressions

Kawasaki Z. Now known as a name that symbolizes super naked bikes, the series is led by the Z1000. The Z125PRO that we test rode this time is its youngest model. It is a minibike with 12-inch tires on both the front and rear. REPORT: CHIKATA Shigeru PHOTO: YAMADA Shunsuke *This is a re-edited version of an article published on September 7, 2018. Prices and color variations may differ from current versions.

https://motor-fan.jp/bikes/article/49593

“Bore-up” is the process of increasing the bore diameter of the piston and cylinder. This is a tuning technique that increases the intake volume of the air-fuel mixture and increases power.

“Bore-up” (illustration above), a standard method of tuning a motorcycle engine, involves increasing the outer diameter of the piston and the inner diameter of the cylinder, in other words, the bore diameter, to increase displacement.

This increases the amount of air-fuel mixture that can be taken in, resulting in increased power. The crankshaft that moves the piston up and down typically uses a standard type, or a type with the same size as the standard stroke.

In addition to increasing the bore diameter of the piston and cylinder, there is also a tuning technique called “bore and stroke up,” which involves replacing the crankshaft with an aftermarket part, lengthening the stroke length, and increasing the displacement.

Hyper S-Stage Bore Up Kit Series for Z125 PRO

Compatible vehicles: Z125 PRO (BR125H-A02621 to A16470) *Note: Vehicles from 2019 onwards are not compatible as FI CON TYPE-X has not been confirmed.

*Note: The following parts have an engine displacement of 125cc or more, so they cannot be used on public roads with a Class 2 moped registration. All parts are for competition use only.

Hyper S Stage Bore Up Kit 138cc (N-10 camshaft) … 171,600 yen (tax included) Part number: 01-05-5480

This 138cc bore-up kit includes a 59mm diameter aluminum cast cylinder, 59mm piston, sports camshaft (N-10), FI-Con TYPE-X (injection controller), big throttle body kit, and spark plug.

The cylinder is made of all aluminum with ceramic plating, which is durable, airtight, and has excellent heat dissipation. The piston skirt of the aluminum cast piston is molybdenum coated to improve initial break-in.

Compression ratio: 12.3:1 (standard: 9.8:1)

Bore diameter: Φ59mm (standard: Φ56mm)

Stroke length: 50.6mm (uses standard crankshaft)

Hyper S Stage Bore Up Kit 138cc (N-20 camshaft) … 171,600 yen (tax included) Part number: 01-05-5481

This kit includes the high-speed camshaft “N-20.” Other than the camshaft, the parts are the same as the “Hyper S-Stage Bore Up Kit 138cc (N-10 Camshaft)” mentioned above.

Hyper S-Stage Bore Up Kit 178cc SCUT (N-20 camshaft) … 180,400 yen (tax included) Part number: 01-05-5482

This 178cc bore-up kit includes a 67mm diameter aluminum cast cylinder, 67mm diameter SCUT piston, sports camshaft (N-20), FICON TYPE-X (injection controller), big throttle body kit, and spark plug.

Compression ratio: 11.5:1 (standard: 9.8:1)

Bore diameter: Φ67mm (standard: Φ56mm)

Stroke length: 50.6mm (uses standard crankshaft)

Hyper S Stage Bore Up Kit for Z125 PRO Series Common Accessory Parts

Sports camshaft (N-10/N-20)

Improved output performance with an optimal cam profile that maximizes performance with a stock cylinder head. Equipped with the same auto-decompression mechanism as the stock. Available in two types: the standard N-10 and the high-speed N-20.

 FI CON TYPE-X (injection controller)

By installing the Takegawa Special Parts bore-up kit and sports muffler, the air-fuel ratio will deviate significantly from the ideal, so it is necessary to correct the fuel injection time with the FI controller shown in the photo. This product can be used by simply removing the coupler from the original ECU and connecting it.

The FI CON TYPE-X has multiple built-in settings tailored to the special Takegawa engine parts. You can easily select, change, and modify the setting data using a PC or smartphone to match the engine specifications.

The injection time can be adjusted up to 5000μs for increase or 7500μs for decrease, making it compatible with a wide range of vehicles, from stock displacement to bore-up.It also has a function for monitoring engine speed, engine temperature, throttle opening, and injector opening/closing ratio using a PC or smartphone, which is very convenient when setting up.

FI CON TYPE-X Manufacturer’s official website　http://www.takegawa.co.jp/products/detail.php?product_id=4277&category_id=1864%3Cbr%20/%3E

Big throttle body kit Φ34

It achieves improved power output at high RPMs, something not possible with a stock throttle body, and allows for stress-free engine performance.

・Includes an air filter for the big throttle body (with blow-by union)

・Includes our original inlet pipe (for stock cylinder head)

・Shroud stay (steel, black painted)

The left and right shrouds can be fixed with the same fitting as the original. The shroud stays can also be used to install a Takegawa oil cooler. By purchasing the Takegawa oil cooler kit separately, the oil cooler can be placed inside the shroud.

※スペシャルパーツ武川製シュラウドステー装着車専用オイルクーラーキットを装着するには、スペシャルパーツ武川製スペシャルクラッチカバーの同時装着が必要。