Three should do on a calm day (that's 6.4 days per year).
I got some tie-downs from the Warehouse for about $6 each that worked well. The ones they provide are just rope. They work OK but, not wanting to sound like a big blouse sheila, they are dirty. Your bike and hands end up black with oil, grease and crap.
My first solo ride over years ago I didn't realise bike owners had to secure their own vehicles. So I pull in, on to centre stand and off upstairs unawares. I got a shock on my return seeing all the other riders removing ropes from their bikes but my baby stood there proudly unmoved on its stand!
MD
Happiness is a means of travel, not a destination
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