Engine Tension Spring Medium Doppler yellow Peugeot 103 \/ MBK 51

Engine Tension Spring Medium Doppler yellow Peugeot 103 \/ MBK 51, spare part for the Doppler ER1 engine springs that are used to stabilize the engine at high rpms. The spring is placed between frame and engine; it stabilizes the movement of the engine and adds resistance to the variator opening.

The spare springs are available in different strengths; a harder spring means more resistance to the variator opening which can lead to better acceleration. The original (hard) spring may be a little too strong for less powerful engines, so Doppler decided to offer an additional softer version.

Yellow = medium (softer than original Doppler spring)