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  1. #1

    95 Fuji 750 - How do I know if my cylinder is shot or not?

    This burn through (see attached photo) on the mag piston happened after installing a triple outlet fuel pump and someone claiming to know how to adjust carbs set all low speed screws to 3/4 turns and all high speed screws to 1/2 turns.

    I (obviously) don't want to have anything to do with that person again and have done lots of reading on here but I still don't know if my cylinder needs replacement or not. If the cylinder seems fine, should I order a brand new piston or can I get a used one that's in good condition?

    Other pistons are showing no signs of caving, however they are all fouled like the burned one in the photo below.

    What next?

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  2. #2
    Click avatar for tech links/info, donation request K447's Avatar
    Join Date
    Jul 2007
    near Toronto, Canada

    Click below for the service manuals, and other useful info.

    You need to measure the cylinder diameter (or the piston, once you have it out) to know what size piston will be required.

    A machine shop can check the cylinder for you, and measure it accurately for wear, taper, and size.

    If it needs to be bored, ask the shop what size they would over-bore it to. Then order that size piston, rings and bearing. Then take it all to the shop, and they will bore the cylinder to exactly match that piston.

    Check the compression on the other two cylinders. If they are low, now would be the time to do all three cylinders together.

  3. #3
    Ok so basically you're saying every piston/cylinder pair will wear out differently? The local junk yard has one of these fuji motors so all I need is a matching piston and cylinder assuming they are in good shape?

    will check compression on other cylinders, thanks for your advice.

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