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XJ400 engine noise

Discussion in 'XJ Technical Chat' started by Bigmacke, Nov 23, 2020.

  1. Bigmacke

    Bigmacke New Member

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    Hello, i recently bought a 1982 Yamaha XJ400, when getting it home i noticed that it made a weird clunking/ticking noise from the engine, some guys told me to check the valve clearance, i did and 2/8 valves were too tight so it shoulden't be the valves that are making the noise.

    The bike has a pretty rough idle and plug 1 & 2 are kinda white while plugs 3 & 4 are black after just starting the bike up a few times.

    I appreciate all the help i can get!

    I am new to the forum, not sure how to upload the video ("The uploaded file does not have an allowed extension") and i can't post the link to my reddit thread.
     
    Last edited: Nov 23, 2020
  2. Yammaat

    Yammaat Active Member

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    Seems a carbcleaning/readjustment could be in order to start with.
     
  3. a100man

    a100man Well-Known Member

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    Turn the idle up. If it sounds better then it could be primary chain clatter which is fairly common I think. Also make sure cam chain is tensioned.
     
    k-moe likes this.
  4. hogfiddles

    hogfiddles XJ-Wizard, Host-Central NY Carb Clinic Moderator Premium Member

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    Check the exhaust collar nuts
     

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