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  1. #1
    CB750 New Member No carbs's Avatar
    Join Date
    May 2020
    Location
    Uk
    Posts
    2

    Compression down on 1 cyl

    Hey

    Been running through some issues with this bike.
    Though it was carb related or spark ,compression test today results cylinder 1 down to 100psi the rest @ 150 cold.. put some oil in cylinder 1 compression cane straight up to 150..

    Any advice much appreciated

    Thanks

  2. #2
    CB750 Guru amc49's Avatar
    Join Date
    Sep 2015
    Location
    Fort Worth TX.
    Posts
    2,909
    Something wrong with it if the number is real, 100 psi is a dead cylinder that will wetfoul a plug in minutes.

    Could be rings stuck from the long sitting, the story may not end well if it was sitting outside in the weather though.

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