How to adjust the valve clearance on the scooter?

Many owners of scooters with four-stroke engines know that the valve clearances must be adjusted. But due to inexperience and ignorance, they do not pay proper attention to this procedure. But in vain. By adjusting the valves on your engine, you will not only improve the stability of its operation, but also extend the life of the engine. It may seem that a few fractions of a millimeter do not greatly affect the performance of the scooter.

However, practice shows that too small or too large valve clearances accelerate the wear of engine parts several times, helping to reduce the time of its work at times. Let us answer the question of why this is happening.

Normal valve gaps for scooters (engine capacity 50-100 cm3) are about 0.05 mm. This value is the same for both the exhaust and inlet valves. However, if it is increased, then the engine starts to knock. On hearing at idle speed, this engine operation is heard as a treading of a sewing machine.

But the trouble is not this. Increased thermal gaps in the valves shift the valve timing. Therefore, when the engine is added to the rpm, the scooter's traction is reduced, fuel consumption and wear of the valve mechanism are increased.

When the valve clearance is more than necessary, then the engine is in an even more deplorable state. After all, there is a loss of compression from the fact that the gaps, heating up, become even smaller, slightly opening the valves. There is a breakthrough of gases and a loss of power. There may also be a burned valve or its seat.

After this trouble, the scooter does not move well at all. His power is lost and candles turn black. Therefore, there is nothing left to do but to replace the valves or even the entire head.

Better once a thousand miles to adjust the valve clearance on the scooter than to buy new parts. To do this (for example, for Alpha and Delta), you need these tools:

- a set of keys;

- a set of probes;

- Pliers.
But do not forget that adjust the valves with a cold engine (when the air temperature is minus, then it is slightly warmed up). The work process is reduced to the following operations:

- Twisting candles.

- Installation of the piston in the TDC (end of the compression stroke), thereby releasing the valves. To check this, it is necessary to unscrew the stopper on the crankcase cover and, turning the crankshaft, ensure that the "T" mark is exactly in the middle of the hatch. Using a key, unscrew the stopper and, turning the screw on the rocker arm, make the adjustment. This operation should be done carefully, so as not to damage the screw, which is often plastic. Measure the probe gap, which at a thickness of 0.04 mm should pass freely, and at 0.06 at all not prolazit. A 0.05 mm probe should not be easily inserted.

- Twisting all the plugs and candles back to their seats.

That's all. As you can see, there are no special secrets here. Now you can start and warm up the engine. With the correct adjustment, you immediately determine by ear how quiet your scooter has started to work and how nice it is to go.