My rack specifically has them Dolphinboy. I presume to aid stability and provide a backup in case the tilting mechanism fails.

Should anyone discover this thread with a view of a robust lightweight heavy handling 4 bike tow hitch carrier.
I can not recommend enough the BuzzRack Buffalo 4.

Click image to enlarge

Click image to enlarge

https://www.roofbox.co.uk/scripts/rbvehsel...02NMX5K%40

Ive still got one of these with the adapter for a 4th bike, I don't use it now as I only move one bike and it's a bit of overkill for that but it was great and probably still is great. In fact I should sell it as I won't ever use it again. Geoff

Supershuttle that looks exactly the sort of upgrade id be interested in! Can't pm you but if you do move it on please let me know.

not any use for newer RR owners with deployable towbar, but for those with the older 2" receiver hitch, JLR sourced these from Westfailia, then the 4 bike Yakima carrier is really really good IMHO

have had it for over 10 years and it is solid, easy to use, and you can open the rear tailgate with the bikes on the rack, this was the reason I originally bought it in the first place

we have also put two e-bikes on it recently, with towbar carriers all the weight of the bikes is downward on the tow ball, but Yakima designed my one to slot into the 2" receiver hitch, which I much prefer being the engineer inside of me

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