I use water-soluble gel, like KY jelly or a generic equivalent, a light schmear on the inside of the boots and around the metal spigots. Vaseline also works. You don't need much!
Here's a way I have done the 'seating' of the carburetors, an appropriate term for my method.
https://www.vmaxforum.net/threads/1989-vmax-resurrection-thread.53264/page-2#post-535165
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Yes, Fonzie started out on a H-D Knucklehead, before a Triumph was used as a replacement. The VOLO Museum by Chicago, rents-out the Knucklehead for $4,000 a day.
Here's a way I have done the 'seating' of the carburetors, an appropriate term for my method.
https://www.vmaxforum.net/threads/1989-vmax-resurrection-thread.53264/page-2#post-535165

Yes, Fonzie started out on a H-D Knucklehead, before a Triumph was used as a replacement. The VOLO Museum by Chicago, rents-out the Knucklehead for $4,000 a day.