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Engines and Components› Pistons and Piston Rings

Polini

154cc Aluminum Performance Cylinder Kit [60mm Bore, 15mm Pin]

$929.01 $863.14 Save $65.87

SKU: 146.0800

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Special Order
Ships in 4–6 weeks
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$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Polini cylinder kit is a 154cc aluminum performance thermal group designed for 125cc 2-stroke engines. Featuring a 60mm bore and Nicasil coating, this kit includes a cast iron bisegment piston with a 15mm pin.

This sport-class kit is compatible with Rotax 122 and 123 engines, providing sharper acceleration and a more direct riding feel. Please note that this unit is delivered without a cylinder head cover.
Show original supplier description
The Polini cylinder kit is a 154cc aluminum performance thermal group designed to upgrade 125cc 2-stroke engines. The cylinder is constructed from aluminum with a durable Nicasil bore lining and features a 60mm diameter, which increases displacement from the stock 125cc to 154cc. The kit includes a cast iron bisegment piston with a 15mm pin and a high-compression cylinder head for improved thermal efficiency. Engineered for sport-level performance, this kit is compatible with liquid-cooled Rotax 122 and 123 engine platforms. Please be advised that the cylinder is delivered without a cylinder head cover; ensure your existing cover is compatible or sourced separately. This kit is confirmed for use with a wide range of Aprilia motorcycles, including the AF1 Futura, AF1 Replica, AF1 Sintesi, Europa, Pegaso, Red Rose, RS 125, RS Extrema, RX 125, SX 125, Tuareg Rally, and Tuono 125, as well as various go-karts utilizing the compatible Rotax engines. Professional installation is generally recommended for thermal group upgrades to ensure correct clearances and engine timing.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandPolini
Part Number146.0800
CategoryEngines and Components
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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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