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Converting to liquid cooling is a very big and complicated step in tuning your engine.

Converting the Cylinder
Some air cooled cylinders can be converted to liquid cooling by adding a water liner around the outside. This is only possible with aluminum cylinders, i.e. Vespa PX 200 Malossi and Lambretta TS1. These aluminum alloys are easily weldable. Much more important is that the bolts in these cylinders are encased in a channel, which means they are separated from the cooling liquid. Cylinders with open bolts, visible from the outside, can hardly be sealed. We do NOT have a satifactory solution for this type of cylinders. In the process of converting a cylinder, circa 70% of the chill ribs are removed from the center and 1.5mm aluminum sheet metal is formed around the cylinder. Before welding everything together, the position of the water inlet and outlet connectors has to be determined, since a separator has to be installed inside. This separator forces the water to flow around the liner and not just from inlet to outlet. Both connectors - parted by the separator - should be as close together. It is also important to add bleeders at the highest points of the circuit, to enable a problem and air bubble free filling. It is often enough to weld a small 8mm aluminum tube to the highest point of the cylinder and seal it with a plug.

Allow about 3 to 6 weeks for a Liquid Cooled Cylinder Conversion

Liquid Lining on a Malossi 210 or TS1 - 330 EURO

==>> Attention:

It absolutly necessery to replate a welded barrel, because there is to much heat and the barrel is defenetly crooked. You can't see with your eye but it is.

typically it takes 4-6 weeks to replate a cylinder

replate a 70 mm bore 239 EURO

Cylinder Head
Closed Circuit. The cylinder bolts do NOT touch the cooling liquid. NO hassle with leaking coolant. We do not offer standard mass production cylinder head. We actually think this impossible, since every customer has different requirements for his cylinder head. Be it the position of water inlet and outlet connectors, combustion chamber form (squish and geometric compression) or the individual placing of threads for themoswitches and sensors. As with the cylinder a separator has to be installed between the connectors to ensure the proper circulation of the cooling liquid. If the connectors are positioned on opposite sides of the cylinder head, a separator is not necessary. The cylinder heads are manufactured to the customers order. Every kit contains 4 thick stainless steel washers for mounting unter the cylinder head nuts. We have 4 custom designed cylinder heads for the PX 200 with Polini 207 or Malossi 210 in our Onlineshop.

Allow about 2 to 4 weeks for a custom built Liquid Cooled Cylinder Head

Liquid Cooled Cylinder Head built to your specifications - 299 EURO

Radiator
A note to the beginning, usually radiators are unfortunately considerably undersized. A small radiator, hidden under the cowl will fail at 35°C on the Autobahn. A radiator has to be exposed to the wind.

The motorbike radiators that are currently available on the market do not really fit nicely. Water in- and outlet, as well as the cap are unfortunately often located in the wrong spots. Mounting brackets are often not present. But we can help, we modify radiators to your specifications, so that you don't have any trouble with the location of the connections, plus we add mounting brackets where you need them. Important is that the radiators get mounted with rubber vibration dampers, this prevents tension cracks and excessive vibration. All radiators are pressure tested in a water bath with 2 bar ( ~29 psi ) to ensure absolute tightness, even with the most extreme modifications. We stock several used radiators, just ask what we have.

Radiator Modification - from 20 EURO

It is also possible to build custom radiators from scratch. We use only high quality aluminum racing radiator cores from a german manufacturer - these outperform the "italians" by far - i.e. Polini.. The cores can be manufactured in a wide variety of basic sizes. We complete them to your specifications with frame, connectors, mounting brackets and the cap. The Vespa T5 and the Lambretta Sprint Racer do have this type of radiators (Gallery).

Custom Radiator - from 350 EURO

Waterpump
We exclusively use Bosch 12V DC waterpumps (see Onlineshop). We also sell the matching rubber dampened mounting brackets.

Temperature and Temperature management

The temperature in the cooling system is very important. Excessive heat may damage the motor, too low of a temperature will also shorten the life of your motor as well. The waterpump is controlled by a thermo switch. We have those in different temperature ranges. I.e. a 70/75°C switch, installed in the cylinder head will engage the pump when the temperature reaches 15°C and turn it off when the temperature drops under 70°C. Preferably we use thermo switches with a lower range, i.e. 60/65°C. To be able to do that the radiator has to be sufficiently large dimensioned. A rule of thumb is, that the pump should run between 15 and 20 seconds, but should be OFF for at least the same period. If this is not the case either the radiator is undersized or the thermo switch is to "cool". Thermo switches over 70/75°C are not feasible, we do not sell switches higher than 70/75°C. To be able to fill the system air lock free, the pump should be able to run permanently (with cold water). In order to enable this, it makes sense to integrate a three position control switch in the system to turn the pump OFF, ON and Thermo switch controlled.

To be able to monitor the systems temperature you can use a temperature gage (see Onlineshop).