The law states that you must present proof of ownership, registration and insurance. It doesn't say that they have to be originals nor does it prohibit you showing that information electronically.
I've been pulled over on my truck and motorcycle and have provided pictures on my phone for proof of ownership, registration and insurance.
It is a terrible idea to keep that information in your vehicle, especially a motorcycle because should it be stolen, it would be easier for the thieves to misuse your information and identity.
Furthermore, keeping the original proof of ownership outside your home is equally just as bad because somebody could forge your signature and claim you sold them the vehicle, as silly as that sounds.
So you need to protect yourself by only having copies of this information, either on paper or on your electronic device and keeping it with you at all times so that you know you have it.
Finally... unless the vehicle is new, or has been recently plated or insured, all of this information will be accessible by the officer that pulled you over so if you are polite and respectful, they will not issue you fix-it tickets and waste both your and the courts time with you showing up to court with the correct documents as they will know this information already and that you are legal.
Don't do it. One time I got stopped by police and only had photocopies and the cop asked me do you take a photocopy of your passport whenever you go for vacation? Why should I not give you this ticket when you are not allowed to go to another country with a photocopy of your passport.
Wham! $310 dollars in tickets.
A police officer is exempt from having to tell you the truth which means they can lie to you about anything in hope that you incriminate yourself and make their job easier.
That doesn't mean that what they say is what the law states.
In the case of the passport, you must physically have that document the same as you must physically have your drivers license to which the law is very clear about those two pieces of documents.
However, your vehicle registration, ownership and insurance do not share the same requirements and therefore can be presented in any manor, as copies or digitally.
EDIT: I've been using photocopies of my registration, ownership and insurance for almost a decade and never had any problems when pulled over by police and in most recent years, I've been using digital copies because its easier and they can always verify the information on their computer anyway so the burden on me to present evidence of my reg, ownership and insurance was fulfilled.