What is Spindle Slider Crash Protection? Protecting the front wheel spindle retainers, brake calipers and lower forks the Front Spindle Bobbins for the Ducati Multistrada V2/V2S are discreet yet resilient protection. Spindle bobbins of black injection-molded nylon sit either side of the front wheel intending to be first to receive impact should an unlikely incident occur. The bobbins sit over an aluminum inner, which adds strength, whilst the bobbins are still free to move with impact to reduce stress and wear.