Some of the current wheels are coming with very sharp outer edge/faces. Since Vegas are already smaller at the bead, you may want to smooth the wheel edge with some fine sandpaper or even a file before mounting.
Use plenty of mounting lube too, and it helps if the tire is warm.
You should not be getting any leaks.
If you do, CA glue can work, or a small amount of silicone as mentioned above.
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Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz www.CarlsonMotorsports.com Carlson Motorsports on Facebook 32 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407 bcarlson@CarlsonMotorsports.com