Dynojet is a tuner for bikes that are already EFI
I started by building my own and was in the process of writing the software when I discovered the guys in the UK that were miles ahead using the same hardware. So I abandoned my project and adopted theirs.
It is an open source (meaning free) software/hardware solution to EFI.
Meaning you can take their software and modify it to suit youself or use it as is. Yu can take the hardware design and make you own boards or purchase one from several suppliers.
It is called speeduino and was started by a guy in the UK named Josh Stewart. I joined his online forum and slack group and just watched and learned for a couple months. When I thought I had a grasp of his product I ordered one and did my first build on a Honda Magna about 2 years ago. I did my second one on a Connie C10 last year and I am now working on my second Connie with a few enhancements over the first. I have had a ton of fun. All the hard work pays off when your cranking it and you hear that first cough..cough..cough.. You know you are getting close.
If you want to look into it, the product is called speeduino . you can buy it from several vendors. the software is free and there is a forum similar to this with lots of knowledgeable people that can help you through your struggles. I am a fully baptized member of the forum.
Check them out. The forum
https://speeduino.com/forum/index.phpSlack
https://app.slack.com/client/T09MSCUFM/C282KTG6RSpeeduino wiki
https://wiki.speeduino.com/en/home