The best tubeless spoked wheels have the spokes anchored at the outer edge of the rim like BMW does with their GS bikes.
Before you attempt to re-seal your wheels, you should have them trued by a competent shop that can build/lace a wheel. Maybe they can seal it too.

 

Please do NOT do this. Coolbreeze, if you are not familiar with the process, please don't give out this kind of information. You will get someone killed. Silicone is NOT an acceptable repair for this type of rim. The entire rubber strip must be removed and completely replaced by a competent shop. Tires on our motorcycles are not to be experimented with. We only have 2, lose one and bad stuff can happen.

 

On a tubelesss spoked wheel like the OP has there is a vulcanized rubber strip that is sealed onto the inside of the rim. This is completely different than a rubber rim strip which is used when replacing the tube in a tubed tire. Also the pressure involved inside of a tire makes RTV silicone a poor choice for a cure. A rubber inner tube patch "may" work, providing you clean, prep the area properly, and the adhesive seals completely around that patch, adhering to the vulcanized strip. If I were the OP I would give a rubber patch a try. I don't think that you would have a catastrophic failure if it were to not hold. You might get stranded on the side of the road. Then the fix would be to add a tube to it.

 

I used to replace the "rubberband" on a spoked rim whenever I put on a new tire.
The original intent was to keep the spoke caps from wearing directly against the tube.
Regardless of tube or not, a new band won't hurt.
Dealer has them. Get the right size. Don't try to repair it. It's your life.

 

This is NOT the "rubberband" you are referring to. It is a vulcanized process to SEAL the spoke nipples.

 

Doesn't matter, leave it there and put a band and a tube. Done deal.