Jiu Jitsu Black Belt

Judo competition is quite soft, but my main martial art is Brazilian Jiu-Jitsu. After earning a black belt in BJJ could I participate in judo peak?

It depends on the tournament. All of the judo ranks are awarded by national bodies in collaboration with your Chief Instructor. These organizations (USJA, USJF and USA Judo) all give you a membership card that has your rank on it, and these grades are used to determine whether you are allowed to compete in advanced competitions. In addition, all the tournaments I've been to require that all competitors must be members of one of three organizations for insurance.

If I were you, I'd take judo classes along with your BJJ. This way, you do not get your BJJ black belt and fighting white belts in judo, where many of your memories BJJ, especially your armbars was unlawful.

Yes, I am a judo teacher