I would use the carbs as well, I like them better and it would make the swap easier. I have an 865 sitting on the floor for a project I hope to start soon and I see no reason it wouldn't be a direct swap for my 790 if I ever wanted to (I don't).I plan to run carbs on it in my project. I am still in the process of getting my new shop together, hard to do being on call 24hrs 3 days a week. I would upgrade the carbs while you are at it if you can find the cash. Not sure I would swap your cams given the oil issue and mileage. If you do have them inspected closely.

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