Gidday Zippo
I agree about the multiple bolts being a good idea.
However, the bike rack I have was designed to take three full size (adult) bikes, and is very strongly attached, with a large circular 'foot' plate, and a tow ball sized bolt that attaches it to the tongue, at tow ball type torque (150+ ft.lbs). The adult bikes in those days weighed about 8-10 kgs each (steel frames etc), so the pole should easily support a 20 kg spare wheel, specially considering that the bikes were mounted rearwards of the pole, and one could possibly mount the spare forward of it. Even if not, the spare has far less drag, and would be more central over the attachment point than the bikes were.
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The rack has a 70 mm (D) x 12.5 mm (T) foot on it, with a ~45 mm post. I do recall that it flexed a bit with bikes on it, but we didn't lose any, even at highway speeds ... :iconwink: :lol:.
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Anyway, I prefer to have these sorts of things in/on a trailer. Gets the weight off the vehicle's wheels and suspension. The trailer axle, suspension and wheel bearings are far stronger and more robust than those of my Forester ... The trailer is engineered around a GVM of about 1,200 kgs, and by law cannot weigh more than 750 kgs gross; the coupling is rated to 2,000 kgs; so well and truly over-engineered.
As we have discussed before, the decision to tow a trailer or not is very much a personal decision. For me, it comes down to being safer and more comfortable with less strain on my vehicle, with some occasional inconveniences as regards parking and taking some hit on fuel economy.
I am also too old and buggered to rough it now, and it's far easier and far quicker for me to erect and pack my trailer tent than it is to erect and pack my 2.6 x 2.6 m Crusader tent. The trailer tent is also infinitely more commodious and comfortable. That's all very important at my age ...
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