Cylinder 72cc GY6 / Kymco 4-stroke / 139QMB/QMA
Description
Tuning Cylinder 72cc for all GY6 / Kymco 50cc 4-stroke models with 139QMB/QMA engine. The perfect choice if you want to upgrade your 50cc stock engine for small money.
The cylinder is not meant for extremely high rpms, it shines at the lower rpm range. It provides constant and very good acceleration even just above idle speed without put excessive load on the engine with unnecessarily high engine speeds.
The cylinder comes with piston and gaskets. The cylinder head is not included, please use the original one. You can keep using the original carburetor but it will require adjusting the main jet.
A 47mm bore means that displacement is 72cc. These 47mm kits are often sold as 80cc cylinders because that's how they are sold in Asia. By the way, 47mm cylinders are actually the cylinders QMB/QMA engines were equipped with originally. It was only to be able to sell vehicles that comply to European driving license regulations that Asian manufacturers started equipping their scooters with 39mm cylinders / 49cc.
How to Install a cylinder on a scooter, motorcycle or moped
The cylinder or cylinder kit is the heart of the engine on scooters, motorcycles and mopeds. It consists of a cylinder, a piston with piston ring(s), a cylinder head and gaskets needed for installation.
The service life of a cylinder depends on whether it has been fitted correctly.
Tuning Level: Sport
We categorize our products into different performance levels Original, Sport, Racing and High End , so that our customers can choose the right parts for their setup. It is really important to combine parts that belong to the same tuning level, this is especially true for cylinders, crankshafts and exhausts.
The products listed under Sport yield better performance than Original parts. They may have technical differences, such as the use of higher quality materials, a larger displacement or a performance-enhancing design. They are suitable for everyday use and have a long service life.
Aluminium cylinders
Aluminium cylinders are more powerful than cast iron cylinders, but require more regular maintenance and must be combined with different components such as a reinforced crankshaft and a larger carburetor.
How to run in an aluminium cylinder?
Aluminium cylinders should be run in for about 200 kilometers , and you should use a fully synthetic engine oil.
Note: To ensure optimum performance and reliability, it is advisable to measure the squish clearance. Just have a look at our tutorial How to adjust squish clearance.
| Cylinder 72cc GY6 / Kymco 4-stroke / 139QMB/QMA | |
|---|---|
| Article no. | BT27365 |
| EAN | 9900000015404 |
| Weight | 1,02 kg |
| Brand | Standard Parts |
| Product type | Cylinder kit |
| Tuning level | Sport |
| Displacement | 72cc |
| Homologation | No |
| Piston pin | 13 mm |
| Cylinder material | Aluminium |
| Bore | 47 mm |
| Stroke | Original |
| Conrod length | Standard |
