What should I do? I'm angry about my significant other buying a brand new motorcycle!
Why are you angry that he bought it?
I've been wanting a new motorcycle so I can go on a riding date, but I wanted to pick it out.
I can understand why you are upset about the situation. It's understandable to be upset at your significant other for making a big purchase behind your back. You should communicate how you feel with him so he knows for the future.
I'm going to cut him off because of this.
It's fine to be upset about your partner making a big purchase behind your back. Instead of cutting him off, you should talk to him about how you feel and give him an opportunity to remedy the situation.