Engine clamps

The different types of motor clamping:

Here you will discover the different types of engine jams and how to avoid them, all with the knowledge and equipment of 2024! I will share my experience with you and help you avoid the same adventures as us.

Overheating tightening:

Definition :

Overheating is when your engine exceeds its operating temperature, i.e. for a cast iron cylinder around 70°C but the tightening only occurs at around 90°C and for an aluminum cylinder the operating temperature is around 50-60°C and the tightening is at around 70-75°C.
(Approximate information values, a tightening can happen at any time.)

During hot summer days, your cast iron cylinders will withstand the heat, but aluminum cylinders will struggle. You'll need to find a way to cool them more and faster. That's why we offer dual radiators on our website.
This will keep your engines cool enough. However, when you, like us, enjoy cruising at full throttle on country roads or highways, your engine may still get very hot after a while.
So, a little reminder, do not force it when your engine reaches 65-70°C (aluminum cylinder) or 90°C (cast iron cylinder) because your engine, even if you release the gas, will continue to heat up! To cool it down and lubricate it, do not hesitate to apply the gas while holding the clutch or even pull the starter to fill it with fuel and avoid breakage!

Cold tightening:

Definition :

A cold squeeze is when your piston expands faster than your cylinder, this generally happens in winter, in summer the engine heats up much faster so there is less of a problem.

In general, it is recommended not to use the engine at its maximum performance until it is close to its operating temperature, but during low temperatures in winter, your engine will tend not to reach its optimal operating temperature which is around 50°C for aluminum and around 70°C (or 55-60°C in winter) for cast iron. To remedy this, the simplest technique is to hide the radiator fins that face the wind with cardboard and/or tape.

Others remove one of the 2 radiators or plug the circuit of the 2nd radiator, but the most professional technique remains to install a thermostat (or calorstat). Be careful with those that are originally supplied for your motorcycles, they are often designed for cast iron! Therefore not adapted to the temperatures of aluminum cylinders. You still have to find either a thermostat that is originally installed on aluminum cylinders or karting thermostats that attach to the hoses. In this case, you must find ones that are mounted on your hoses and that open around 40-50 ° C for aluminum cylinders and 55-60 ° C for cast iron.

Tightening due to lack of oil :

Definition:

Low oil tightening is simply when your engine runs with less oil than the minimum recommended quantity.

A 2-stroke engine runs on a mixture of oil and gasoline and it is this oil that will lubricate it unlike the 4-stroke where we have an oil pan and a pump which allow to always have a thin film of oil between your different engine components.
You must run between 2 and 4% oil. 2% is the minimum to avoid tightening, my advice is to always run at 2.5% you will never have tightening problems or engine fouling. 3% For running-in, above it is not necessary.

Tightening due to poor internal clearance:

Definition :

Tightening due to poor cylinder-piston or ring clearances is when your piston or rings have too tight a clearance with your cylinder and therefore do not have the room to expand fully.

To avoid this, remember to check your clearances carefully. For your cylinder-piston clearance, it must be at least 0.05 mm. Basically , it must slide easily into your cylinder , not rub and go down with difficulty. Otherwise, you risk tightening ! To increase this clearance, you can try using a honing tool. Or, when replacing your piston, take the correct piston size.

For the segment cutting game, this is just as important!
It must be at least 0.15mm and at most 0.35mm, the more compression losses you will have.
I recommend 0.20 to 0.25mm, it's perfect for reliability and performance, 0.15mm is a value reserved for the cylinder rotating in run.