Kirby Speed Switch Spring Heritage I

Kirby part 133981S is the small return spring behind the speed switch on the Kirby Heritage I. It gives the switch its snap: work the control and the spring drives the mechanism firmly back into position, so the setting you chose stays put.

When the spring stretches or breaks, the switch turns mushy — it drifts between speeds, fails to snap back, or will not hold high or low reliably. If your Heritage I's speed control has lost its positive click, this spring is the usual culprit and the cheapest fix, fitted during a switch service. Handle it gently on the way in; a stretched spring loses the tension that makes the switch work.

It is a genuine Kirby part, matched to the original spring's tension. The spring is specific to the Heritage I — later Heritage II and Legend machines use different switch hardware, so check which Kirby you have before ordering.