This is called Big Bore kits for pocket bike Blata water cooled.

1) Cylinder bore: 39.5 mm, so it increases much more power. Standard bore is only 37 mm.

2) Use the best and much more high performance new aluminum caps sets which can increase more power and it is with better quality than others.

3) It is with new O rings and head gasket.

4) Use quality spark plug.