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  1. #1

    Join Date
    Jun 2010
    Long Island, NY

    87' JS550 Mikuni Carb

    Hey guys, I was given an 87' JS550 in what i thought to be okay shape but was missing a few things here and there. Threw a battery in it and to my surprise it started but wouldn't stay running. It had sat for some time and i'm very new to this but I was planning on making this a project of mine. My first suspicion is the carb which I've researched and believe to be a 40mm Mikuni Carb. I know most of you guys say not to even bother rebuilding a BN and go straight for an SBN to save myself a headache. My question is can someone tell me if I have a BN or an SBN carb of my hands? I only ask because whoever owned this ski last took the time to make some modifications and I didn't know if the carb was one of them. (ski has a coffman pipe, sponsons removed)
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  2. #2

    Join Date
    Jun 2010
    Long Island, NY
    Stumbled upon a website that showed the difference. This is a Mikuni44BN which in so many words is junk. Looks like i'll be looking for an SBN as the next step to this project.

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